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Rating is 4.8 out of 5.
4.8/5
based on 247 client reviews
  2. Development & IT Talent
  3. Network Administrators
  4. (Current) SIP Specialists
  • $150 hourly

    • 5.0/5
    • (250 jobs)
    A Top-Rated, Expert-Vetted VoIP/Software engineer with over 20 years of experience. My experience ranges from Asterisk/FreePBX phone systems, SMS messaging, Linux operating systems, to network administration. I believe you deserve a more professional, reliable, and personalized business experience, and I bring that mindset to every project. Whether I’m developing top-secret code for Lockheed Martin, or AI telephone agents for Nomo, or creating privacy-first communications for Mecca Hosting, Inc, or designing secure, high availability Asterisk systems for TeleConnx Inc., or handling difficult troubleshooting tasks, I always commit myself to the same standard: creative, client-first solutions and efficient, high-quality work, completed in a fraction of the time. I have a passion for transforming mundane phone interactions into exciting customer experiences, and I lean on decades of experience to create solutions that others would find impossible. In short, I can make your telephone system do pretty much anything, including turning on your coffee maker in the morning. I look forward to working with you!
    vsuc_fltilesrefresh_TrophyIcon SIP
    FreePBX
    MySQL
    Kamailio
    Linux System Administration
    Amazon Web Services
    VoIP Administration
    Asterisk
    API Development
    C
    VoIP Software
    LAMP Administration
    Session Initiation Protocol
    Linux
    VoIP
    Business with 10-99 Employees
  • $75 hourly

    • 5.0/5
    • (62 jobs)
    I have over a decade of VoIP networking experience deploying and configuring iPBX's (3CX, ShoreTel), Skype for Business/Lync, Session Border Controllers and Gateways (AudioCodes, Sonus, Edgewater). My experience ranges from complete project management to individual SBC/GW implementations. My core focus has been VoIP connectivity and the applications that accompany it like Call Recording (Cloud & On-Premise), Office 365 and Exchange. The vast majority of my time has been spent implementing on-premise systems (60%) and hosted systems (40%) for small and medium businesses. I have interfaced with Tier-1 Carriers, (ATT, Verizon, Centurylink, Level(3)) all the way down to pure SIP based service providers such as (G12, Flowroute, PureIP).
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    Phone Communication
    IT Management
    VoIP Administration
    3CX
    Session Initiation Protocol
    Skype For Business
    Network Engineering
    Network Planning
    Network Design
    Network Monitoring
  • $120 hourly

    • 5.0/5
    • (86 jobs)
    • CCNP Collaboration • Configure and troubleshoot Cisco Webex Calling • Transition customers from on-premise to Cisco Webex Calling • Extensive experience and training in designing, installing, and troubleshooting Cisco Unified Communications Manager, Unity Voice Mail, Unified Contact Center Express and other applications, Voice Gateways, and IP Phones • 3 years configuring, troubleshooting, and transitioning customers to Cisco Webex Calling • 22 years of configuring, troubleshooting, and testing Cisco Unified Communications Manager (CallManager) and other Cisco Applications • 24 networking experience • 24 operating system and Microsoft application experience • 24 years of project management experience • 24 years of installing, configuring, maintaining, and troubleshooting Cisco routers and switches
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    Cisco Certified Network Associate
    Cisco Certified Network Professional
    Session Initiation Protocol
    Cisco UCS
    VoIP Administration
    Cisco IOS
    Cisco Router
    Cisco CallManager
    VoIP
    Network Administration
  • $75 hourly

    • 5.0/5
    • (77 jobs)
    "I'm only driven to deliver the best-quality, Hire me if you are looking for the same" My name's Moataz, and here are my qualifications/experiences. - 12+ Years working on VOIP solutions (Avaya in particular) in two countries (Egypt & Saudi Arabia) at big system integrators. - I have done a lot of projects at different segments/sectors with different sizes (SMB & Enterprise, and Megaprojects), starting from legacy systems to the latest technologies. - working on all application types of unified communications and customer experience applications. - Pre-sales experience, and consultancy Expertise: - IP Office, VmPro, Onex Portal, IPOCCS, ACR - Avaya Aura Core Components (SMGR, SM, CM, US, H.245 gateways) - Equinox TE & AAWG - Equinox OTT (MGMT, MEDIA, H.323, Equinox Edge, and Equinox Recording) - Aura Presence with Multimedia Messaging enabled (PMM) - AADS (standalone & clustered) - SBCE standalone and HA for remote worker and sip trunking. - Call Center Elite, AACC, EMC, - Experience Portal, WFO, and CMS - Avaya soft clients (Equinox Client, Equinox Attd, OneX Comm, OneX Agent, OneX attd). - Multiple Avaya portfolios such as (IPT, Hospitality Solutions, and Call Centers) - Different types of Avaya PBX and media gateways (SI, MCC, G450/G430, and G650). - Integration between Avaya and other systems (Astrix, LYNC & CISCO...). - Custom reports for CMS Designer. - Cisco CUCM, Unity. - Grandsteam - FreePBX, Neogeo Router Services: 1- Troubleshooting any raised issue. 2- Preventive/proactive maintenance with a weekly report. 3- New implementation/commissioning. 4- Operation over the clock (already have a team for continuous operation & monitoring) 5- Consultancy sessions regarding design requests, quotations, licenses, and sizing. 6- Training sessions
    vsuc_fltilesrefresh_TrophyIcon SIP
    VoIP
    Solution Architecture
    Remote IT Management
    Session Initiation Protocol
    Network Administration
    Network Design
    3CX
    Cisco Certified Network Professional
    Avaya
    Amazon Web Services
    Cisco Certified Network Associate
    Cisco CallManager
    PBX
    Technical Documentation
    VoIP Administration
  • $55 hourly

    • 4.1/5
    • (58 jobs)
    I have 18+ years expereince in VoIP/SMS setups using IVRs, asterisk , Freeswitch, MS Teams and Opensips/Kamailio and VoIP | Freeswitch | Opensips | Contact Centers| Conversational AI| Amazon Connect|MS Teams
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    Session Initiation Protocol
    CentOS
    Linux
    FreeSWITCH
    Customer Relationship Management
    A2Billing
    Asterisk
    MySQL
    WebRTC
    Android
  • $50 hourly

    • 5.0/5
    • (172 jobs)
    I am consistent "Top Rated Plus" VoIP Developer on Upwork with numerous 5 star reviews including excessively positive feedback. 13+ years of experience in Custom VoIP Software Development. I have provided a wide range of IT solutions, including VoIP Development, Websites & Mobile Apps development for international businesses and start-up companies as well as for large enterprises. 🏆 Following are my area of experiences: ✓ VoIP / SIP / RTP ✓ OpenSIPs / Kamailio / OpenSER ✓ FreeSWITCH, FusionPBX, ASTPP, Lua Scripts ✓ Asterisk, FreePBX, A2billing ✓ RTPengine / MediaProxy / RTPproxy ✓ Twilio ✓ Linux & OpenSource Consulting ✓ MariaDB, MySQL, PostgreSQL (Database design & complex SQL query expert) ✓ PHP, Yii/Yii2, Apache, Nginx ✓ Android 🏆 I provide the following solutions: ✓ High scalable Least Cost Routing(LCR) with Fail-Over ✓ Session Border Controller(SBC) ✓ Click to call ✓ Class4 & Class5 Soft Switches ✓ SIP Proxy Server, SIP Load Balance & Fail-Over ✓ SIP Messaging Server, SIP Redirect Server ✓ IVR Application ✓ Fax over IP (FoIP), T38 Supported FAX Server, FAX to Email ✓ Shoutcast Server ✓ WebRTC SIP client ✓ PHP RESTfull API, Web Services for Mobile Application ✓ Web Applications ✓ Mobile Applications. My core competency lies in complete end-to-end IT solutions for VoIP, Web, and Mobile technologies. 👤 Reviews & feedback given by clients for successfully completion of largest projects ⭐⭐⭐⭐⭐ "Malay is an excellent VoIP expert and was able to do any task we could throw at him. Will be using his services again shortly as our go-to VoIP expert." ⭐⭐⭐⭐⭐ "Excellent at meeting deadlines. Outstanding at changing work hours to conform to my requirements. First-rate productivity levels. Extremely good communication and ability to explain and brainstorm in a group environment. Admirable at working with other random developers I brought into the project throughout the years. Malay and his team at Prayantech were able to tackle any task I through at them from Asterisks, FreeSwitch, Python PHP HTML JS Debian RHEL IP Tables working inside of multiple different cloud hosting environments his understanding of VPN and firewall security are excellent. I can’t say enough good things about this group I am certain we will be working together as a team for many years to come." ⭐⭐⭐⭐⭐ "Malay and his team were great to work with. Once we got in a flow, we were able to bring something to life I could not have done without him and his team. He was extremely aware of timelines and making time for our project during our "open hours" and working around the time change. Thank you Malay! Keep up the great work and I look forward to working with you soon!" ⭐⭐⭐⭐⭐ "It was a pleasure working with Malay. Very professional and to the point. they don't waste time and they want to finish your project as much as you want to."
    vsuc_fltilesrefresh_TrophyIcon SIP
    MySQL
    OpenSIPS
    FreeSWITCH
    Yii
    PHP
    Kamailio
    Yii2
    API
    VoIP Software
    Asterisk
    MariaDB
    Session Initiation Protocol
    Linux System Administration
    Database Administration
    VoIP Administration
    VoIP
  • $40 hourly

    • 4.8/5
    • (25 jobs)
    1. Expert in IP solutions (RCS-GSMA) with open source experiences. 2. Having experience in IMS (IP Multimedia Subsystem) solutions. 3. Having 10 years of experience towards kamailio and opensip projects. 4. Expertise in SIP,SDP,RTP,MSRP,HTTP,DIAMETER,SMPP protocols 5. I can develop custom modules in kamailio,opensip projects 6. Moderate in freeswitch, fusion PBX and asterisk 7. Mainly solution architect in VOIP 8. Well experienced with TCP,UDP and SCTP transport stacks. 9. Well experienced with wireshark and Homer utilities
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    Kamailio
    Session Initiation Protocol
    IP Multimedia Subsystem
    OpenSIPS
    VoIP Administration
    VoIP Software
    Rich Media
  • $45 hourly

    • 5.0/5
    • (22 jobs)
    My experience in the VOIP domain has been for 15 years. My customer satisfaction is my goal. I have extensive experience with Asterisk/Kamailio systems, as well as Linux and network administration. I have the ability to do advanced troubleshooting . My expertise on this: * Asterisk, Kamailio, OpenSips, FreePBX, A2billing, SIP, H323, IAX, Webrtc, hylafax, Asterisk-Pannel, iaxmodem, rtpproxy, MediaProxy, WebRTC, SipML5, SMS API, IVR (Interactive Voice Record),Wireshark * IP routing, router configuration (cisco, iptables routing), switch, Vlan, VPN (Ipsec linux, cisco vpn, fortigate, OpenFire). * Fail2ban, Iptables, OpenSwan, Squid, Cisco FirePower, Vmware, Proxmox * Php, Mysql, Postgresql, sqlite, Mongodb, Bash , LUA , Java, AGI, AMI * Roundcube, Zimbra, Zabbix, Smokeping, munin, Nagios, Cisco NetFlow, Voipmonitor * Git, Ansible, bitbuket, atlassian My time is my value. So when you choosing me you can expect that job will be done in short terms and perfect. I don't like to do something that not need be done. @linkedin linkedincom/in/alaeddine-hertelli/ SKYP:alasupcom1
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    OpenSIPS
    FreePBX
    PostgreSQL
    Wireshark
    Asterisk
    Session Initiation Protocol
    Kamailio
    Vtiger
    Iptables
    MySQL
    Bash Programming
    PHP
    Network Engineering
    Linux
    VoIP
  • $25 hourly

    • 4.7/5
    • (19 jobs)
    Hi Guest, First of all, thanks for visiting our profile. I am doing freelancing since 2010 and my expertise on complete VoIP solution including Freeswitch, Asterisk, PJSip, Opensips and Kamailio. I just recently launched a company which is not offering only VoIP solution but Zeus in Web Development(PHP, WordPress etc), Mobile App Development(Android & iOS). We are a team of members having extensive knowledge of all the services we are offering. We have successfully completed many projects delivered competent results with 100% accuracy with lifetime free support. To keep in mind 100% availability, Our dedicated manager is always online to make sure our client will face no more difficult to ask any query at any time. Let me mentioned the technologies which are our core strength listed below: - Development of Linphone Mobile VoIP Diallers - Development of PJSIP Mobile VoIP Diallers - Installation, development, customization, and maintenance of Asterisk,FreeSwitch Switch,Kamalio and OpenSIPs Servers - Android app development - iOS app development - Flutter Cross Platform App Development - Electron App Development - Web application development - ReactJS and ReactNative development for web and mobile applications - Testing and bug fixing for existing applications Consulting for ongoing projects Project consulting for Android, iOS, ReactJS, Asterisk, FreeSwitch, OpenSIPs, Kamailio, ASTPP, RTPengine, MediaProxy, RTPproxy, FreePBX, and A2Billing Expertise in developing Flutter WebRTC applications Expertise in developing ReactNative WebRTC applications Our price is very reasonable which allows us to work with us. Please share your requirement today only with us to check our capabilities to take your experience on the next level. To name a few tools & technologies that I have worked on: • High-level languages: C++, Objective C, Java, Python, PHP • IDEs: Xcode, Android Studio, Eclipse • Version Control & CI: SVN, Git, Perforce, Bitbucket, Jenkins • DBMS: MS SQL, MySQL, Oracle, PostgreSQL, MongoDB • Frameworks: Django, Zend, Magento, Django REST • Management tools: VersionOne, Jira, Trac, MS Project, MS Visio, XMind, Bugzilla, Balsamiq • Amazon Web Services (AWS) - EC2, S3, SQS, SNS, RDS, CloudTrail, Cloudfront
    vsuc_fltilesrefresh_TrophyIcon SIP
    WebRTC
    iOS
    Android App Development
    AWS OpsWorks
    VoIP Software
    iOS Development
    FreePBX
    AMP Framework
    VoIP
    Session Initiation Protocol
    Asterisk
    VoIP Administration
    FreeSWITCH
    WordPress
    PHP
  • $24 hourly

    • 4.9/5
    • (286 jobs)
    🥇🥇🥇 𝗣𝗿𝗲𝗽𝗮𝗿𝗲 𝘁𝗼 𝗯𝗲 𝗱𝗮𝘇𝘇𝗹𝗲𝗱!🥇🥇🥇 🏆 Behold, the 𝗧𝗢𝗣 𝗥𝗔𝗧𝗘𝗗 𝗣𝗟𝗨𝗦 🏆 in the realm of freelancers, with a prestigious spot in the "𝗧𝗼𝗽 3%" on Upwork! Our credentials speak volumes: ✅ Over 20,000+ hours of dedicated work and counting. ✅ Successfully completed 350+ projects, leaving a trail of satisfied clients. ✅ A flawless 100% Job Success ratio – it's all about client satisfaction. ✅ An impressive 99% of clients recommend us to others. ✅ An astounding 90% of our clients keep coming back for more. ✅ We bring over 12+ years of industry experience. ✅ Delivering unparalleled, high-quality work that sets new standards. ✅ Cutting-edge solutions that won't break the bank. ✅ Verified proficiency in fluent English. 🌟 Whether you're a 𝗦𝘁𝗮𝗿𝘁𝘂𝗽 extraordinaire, an 𝗘𝘀𝘁𝗮𝗯𝗹𝗶𝘀𝗵𝗲𝗱 𝗕𝘂𝘀𝗶𝗻𝗲𝘀𝘀 maven, or simply on the prowl for 𝗠𝗩𝗣 domination, you've found the ultimate source of 𝗛𝗶𝗴𝗵-𝗤𝘂𝗮𝗹𝗶𝘁𝘆 𝗦𝗲𝗿𝘃𝗶𝗰𝗲𝘀 at prices that won't give you sticker shock. 🚀 Ready to embark on a journey towards success? Click that '𝗜𝗻𝘃𝗶𝘁𝗲 𝘁𝗼 𝗝𝗼𝗯' button, and let's chart a course for your project and your vision. 𝗢𝘃𝗲𝗿 𝘁𝗵𝗲 𝗽𝗮𝘀𝘁 𝗱𝗲𝗰𝗮𝗱𝗲, 𝗜'𝘃𝗲 𝘄𝗶𝗲𝗹𝗱𝗲𝗱 𝗺𝘆 𝗲𝘅𝗽𝗲𝗿𝘁𝗶𝘀𝗲 𝘁𝗼 𝗰𝗿𝗮𝗳𝘁 𝗮 𝗱𝗶𝘃𝗲𝗿𝘀𝗲 𝗿𝗮𝗻𝗴𝗲 𝗼𝗳 𝗮𝗽𝗽𝘀 🛎️ 𝗙𝗶𝗻𝘁𝗲𝗰𝗵 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝘆: Payment app, Budgeting app 🛎️ 𝗛𝗲𝗮𝗹𝘁𝗵𝗰𝗮𝗿𝗲 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝘆: Telemedicine app, Health records app 🛎️ 𝗘-𝗰𝗼𝗺𝗺𝗲𝗿𝗰𝗲 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝘆: Shopping app, Delivery tracking app 🛎️ 𝗥𝗲𝗮𝗹 𝗘𝘀𝘁𝗮𝘁𝗲 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝘆: Property listing app, Mortgage calculator app 🛎️ 𝗘𝗱𝘂𝗰𝗮𝘁𝗶𝗼𝗻 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝘆: E-learning app, Quiz and assessment app 🛎️ 𝗧𝗿𝗮𝘃𝗲𝗹 𝗮𝗻𝗱 𝗧𝗼𝘂𝗿𝗶𝘀𝗺 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝘆: Travel booking app, Tour guide app 🛎️ 𝗙𝗼𝗼𝗱 𝗮𝗻𝗱 𝗥𝗲𝘀𝘁𝗮𝘂𝗿𝗮𝗻𝘁 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝘆: Food delivery app, Table reservation app 🛎️ 𝗘𝗻𝘁𝗲𝗿𝘁𝗮𝗶𝗻𝗺𝗲𝗻𝘁 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝘆: Streaming app, Event ticketing app 🛎️ 𝗔𝘂𝘁𝗼𝗺𝗼𝘁𝗶𝘃𝗲 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝘆: Car rental app, Vehicle tracking app 🛎️ 𝗙𝗶𝘁𝗻𝗲𝘀𝘀 𝗮𝗻𝗱 𝗪𝗲𝗹𝗹𝗻𝗲𝘀𝘀 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝘆: Workout app, Nutrition tracking app 🛎️ 𝗦𝗼𝗰𝗶𝗮𝗹 𝗡𝗲𝘁𝘄𝗼𝗿𝗸𝗶𝗻𝗴: Social media app, Dating app 🛎️ 𝗧𝗿𝗮𝗻𝘀𝗽𝗼𝗿𝘁𝗮𝘁𝗶𝗼𝗻 𝗮𝗻𝗱 𝗟𝗼𝗴𝗶𝘀𝘁𝗶𝗰𝘀: Shipping and tracking app, Fleet management app 🛎️ 𝗔𝗴𝗿𝗶𝗰𝘂𝗹𝘁𝘂𝗿𝗲: Crop management app, Weather forecasting app 🛎️ 𝗠𝗮𝗻𝘂𝗳𝗮𝗰𝘁𝘂𝗿𝗶𝗻𝗴: Inventory management app, Quality control app 🛎️ 𝗜𝗼𝗧 (𝗜𝗻𝘁𝗲𝗿𝗻𝗲𝘁 𝗼𝗳 𝗧𝗵𝗶𝗻𝗴𝘀) 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝘆: IoT monitoring and control app 🛎️ 𝗕𝗹𝗼𝗰𝗸𝗰𝗵𝗮𝗶𝗻 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝘆: Cryptocurrency wallet app and Blockchain Solutions 🛎️ 𝗕𝗹𝘂𝗲𝘁𝗼𝗼𝘁𝗵 𝗔𝗽𝗽 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁: Bluetooth-based smart device control app 🛎️ 𝗡𝗙𝗖 (𝗡𝗲𝗮𝗿 𝗙𝗶𝗲𝗹𝗱 𝗖𝗼𝗺𝗺𝘂𝗻𝗶𝗰𝗮𝘁𝗶𝗼𝗻) 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝘆: Mobile payment and contactless communication app 🛎️ 𝗛𝗜𝗣𝗔𝗔 𝗖𝗼𝗺𝗽𝗹𝗶𝗮𝗻𝗰𝗲-𝗕𝗮𝘀𝗲𝗱 𝗛𝗲𝗮𝗹𝘁𝗵 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝘆: Electronic health records (EHR) app 𝗪𝗵𝘆 𝘀𝗵𝗼𝘂𝗹𝗱 𝘆𝗼𝘂 𝗲𝗻𝘁𝗿𝘂𝘀𝘁 𝘆𝗼𝘂𝗿 𝗽𝗿𝗼𝗷𝗲𝗰𝘁 𝘁𝗼 𝗺𝗲? ✅ I am your steadfast ally in your quest for success. ✅ Uncompromising commitment to quality without breaking the bank. ✅ A robust command of Android, iPhone, and backend architecture, alongside database wizardry. ✅ Crafting applications that seamlessly adapt to all devices. ✅ Promising on-time delivery or even before. ✅ A perpetual thirst for the latest technological innovations. 𝗠𝘆 𝗰𝗼𝗿𝗲 𝘀𝗸𝗶𝗹𝗹𝘀 𝗮𝗻𝗱 𝗲𝘅𝗽𝗲𝗿𝗶𝗲𝗻𝗰𝗲𝘀 𝗮𝗿𝗲 𝗮 𝗳𝗼𝗿𝗰𝗲 𝘁𝗼 𝗯𝗲 𝗿𝗲𝗰𝗸𝗼𝗻𝗲𝗱 𝘄𝗶𝘁𝗵 🎯 Mastering the art of backend interaction: Rest API, JSON, XML, PHP, Node.js, Python. 🎯 Databases and data management aficionado: SQLite, MySQL, Parse, MongoDB. 🎯 Seamless social integration: Facebook, Twitter, Youtube, Instagram, Snapchat, Tinder. 🎯 Real-time chat maestro: XMPP, Socket, Firebase, GetStream, Twilio. 🎯 Version control expert: Github, Bitbucket, Gitlab. 🎯 Navigating the world with Google and Apple Maps, Geolocation, GPS, and Location Tracking. 🎯 Making waves in audio and video live streaming. 🎯 Mastery of Firebase APIs. 🎯 Navigating the payment landscape with ease: Paypal, Braintree, Stripe Payment Gateway. 🎯 Scanning the horizon with QR Codes, Bar Codes, VIN Scanner, and NFC Tags Reading. 🎯 Engaging users with In-App Purchase, Advertisement, Push Notifications, GCM, and Google Analytics. 🎯 Elevating photo and video sharing with editing and filters. 𝗜 𝗵𝗮𝗿𝗻𝗲𝘀𝘀 𝘁𝗵𝗲 𝗽𝗼𝘄𝗲𝗿 𝗼𝗳 𝘁𝗵𝗲𝘀𝗲 𝗰𝘂𝘁𝘁𝗶𝗻𝗴-𝗲𝗱𝗴𝗲 𝘁𝗲𝗰𝗵𝗻𝗼𝗹𝗼𝗴𝗶𝗲𝘀 📌 Android: Kotlin, Java 📌 iOS: Swift, Objective-C 📌 Cross-platform (Hybrid): Flutter (Dart) , React Native (Javascript) 📌 Web / Backend: PHP, Node.js, Python, Laravel, WordPress, Express.js, Nest.js, Django 📌 Frontend: React.js, HTML5, CSS3, BootStrap, JavaScript, jQuery 📌 Exploring the realms of AI, Internet Of Things (IoT), Beacons, and Ricoh Theta 360.
    vsuc_fltilesrefresh_TrophyIcon SIP
    NestJS Development
    NestJS
    Vue.js
    Figma
    iPad App Development
    Laravel
    Apple Xcode
    iOS Development
    Node.js
    Swift
    PHP
    React Native
    Android
    Android App Development
    Flutter
  • $50 hourly

    • 5.0/5
    • (20 jobs)
    - Technologies: Kamailio, RTPEngine, Freeswitch, WebRTC, Flexisip, Asterisk - Protocols: SIP, SDP, RTP, websocket - Test Tools: sipp, sipsak, twinkle-console - Debug Tools: sngrep, ngrep, tcpdump, wireshark
    vsuc_fltilesrefresh_TrophyIcon SIP
    VoIP Software
    VoIP
    Ansible
    C++
    Bash
    VoIP Administration
    C
    Network Engineering
    Software Debugging
    Python
  • $60 hourly

    • 4.9/5
    • (44 jobs)
    Having 12 years’ experience in Asterisk/OpenSips/Kamailio based application development. With over 6 plus years’ experience in WebRTC development along with 4 years’ experience in Windows development. Below are highlights of the projects and applications worked on: 1. Worked on all the Asterisk configuration changes, which even includes PJSIP. 2. Asterisk Event module (Which handles the request from NodeJS server and handles the events like play greeting, play MOH, Take input field, record greeting, making call, etc. it covers all the features and functionalities of asterisk) 3. Projects which deal with SIP WebRTC Client both Audio & Video. 4. JSON VOIP Client (Audio & Video). This was developed to overcome the loading of heavy SIP stack in browser or mobile. as a result we develop a simple JSON framework to make calls, with a server in the middle that converts to SIP and pushes calls to the asterisk server. 5. Applications for Video conferencing on WebRTC, which supports Peer to Peer in browsers, Android & iOS systems. 6. Applications for Video on WebRTC with SFU (Janus GateWay) in browser, Android & iOS systems. 7. Windows and Mac-based Video Conference applications. In short, we developed an application that is similar to Zoom Meetings. 8. Technologies used for applications like OpenSips/Kamailio only for Proxy, Registrar, and Load Balancing. 9. Worked on C# wpf WebRTC video conferencing service. 10. Worked on C# wpf PJSIP softphone application along with 11. Worked on electron.js with PJSIP softphone application. 12. Microsoft Teams SBC (Call To Teams) 13. SIP to Whatsapp gateway with freeswitch and lineageos on ubuntu with multiple Virtual machines
    vsuc_fltilesrefresh_TrophyIcon SIP
    Tableau
    Session Initiation Protocol
    FreeSWITCH
    Asterisk
    Desktop Application
    React Native
    C++
    Android
    C
    Microsoft Windows
    Swift
    React
    Flutter
    WebRTC
    C#
  • $85 hourly

    • 4.9/5
    • (27 jobs)
    Hi, I'm Bucky. I'm a consultant specializing in all manner of VoIP services. My experience is mostly on the backend, building solutions around primarily open-source VoIP technologies (Asterisk, FreeSwitch, Kamailio) and cloud provider APIs (e.g. Twilio, Telnyx, and Signalwire) with a sprinkling of proprietary Cisco and Oracle/Acme knowledge thrown in for good measure. I'm happy to handle simple stuff like account provisioning or troubleshooting call quality issues, but I'm also more than capable of taking on high-complexity projects up to full carrier environment setups. One thing that sets me apart from a lot of other freelancers is that this is not a "side-hustle" for me -- this is my full time job. I have an office and a desk phone, and am basically always within 10 steps of a PC. If you hire me for a project (whether it's a short-term endeavor or long term recurring contract), you'll get access to my contact info, and the peace of mind that you've got an on-call telecom expert for emergencies. Before I ventured into consulting, I spent a good chunk of my career working in the telecom industry for "large" competitive local exchange carriers and enterprises. I enjoyed the work but could never find the "value" in what I was doing, so I ultimately made the switch. Honestly, while it's not as profitable for me to help smaller carriers and businesses, helping the little guy and seeing the direct result is a lot more rewarding to me.
    vsuc_fltilesrefresh_TrophyIcon SIP
    VoIP
    VoIP Software
    Twilio API
    FreePBX
    VoIP Administration
    Kamailio
    Terraform
    Asterisk
    Session Initiation Protocol
    DevOps
    Network Engineering
    CI/CD
    Telecommunications Engineering
    Business with 10-99 Employees
    Linux
  • $35 hourly

    • 4.9/5
    • (34 jobs)
    I am a telephony engineer. I have good knowledge of SIP and PSTN. Experience: ● Asterisk; ● Alcatel-Lucent OXE 4400; ● System administrator linux (Centos, Ubuntu); ● FreePBX | Elastix | Kolmisoft MOR | Grandstream UCM | 3CX phone system | ● Pyhton, Bash, PHP scripting; ● GSM Gateway, ATA, SIP phone and etc. ● Zabbix ● Billing system Tariscope ● MySQL and PostgreSQL
    vsuc_fltilesrefresh_TrophyIcon SIP
    Linux System Administration
    VoIP Software
    VoIP Administration
    Grandstream
    FreePBX
    MySQL
    Session Initiation Protocol
    VoIP PBX
    Asterisk
    Ubuntu
    Linux
    CentOS
    Python
    Bash
  • $60 hourly

    • 4.9/5
    • (343 jobs)
    There is some feedback: - Pavel was fantastic! My project hit a snag and I needed an FTP server configured quickly. When I couldn't complete the task myself, I asked for help. Pavel jumped in immediately and had me fixed in no time and friendly answered all my questions. This guy is a real problem solver! - Very smart when it comes to Linux systems, was able to help with our issue. - Very skilled and professional expert who solved all additional and unexpected problems with patience. He overdelivered and I can highly recommend working with him! - The problem was solved quickly and efficiently. - Pavel did a great job tracing the problem and solving it - Pleasure to work with. Skilled system administrator and network engineer with 18 years of hands-on experience. Know how to organise network in one office or in several offices connected via vpn. Unix system administrator, with a lot of experience in Linux and BSD distributions.. I have got working experience with: DNS; DHCP; LAMP-LEMP; FTP; SMTP; SNMP; ACL, firewalls and NAT; I have experience with cloud services (AWS, GCE, Vultr, DigitalOcean) and virtual infrastructure (vSphere, Hyper-V, Proxmox); I have got working experience with Monitoring (Zabbix); VoIP/IP telephony (Asterisk,FreePBX).
    vsuc_fltilesrefresh_TrophyIcon SIP
    Asterisk
    DNSsec
    WordPress
    Linux System Administration
    Firewall
    Apache Administration
    MySQL
    LAN Administration
    Session Initiation Protocol
    Squid
    Web Hosting
    Network Engineering
    VMware vSphere
    NGINX
  • $90 hourly

    • 5.0/5
    • (32 jobs)
    Over 10 years experience with Cisco Collaboration products including Call Manager, Unity Connection, IM&P/Jabber, Expressway, Emergency Responder, Webex Meetings/Calling/Contact Center and etc. CCIE Collaboration certified. Mwraki, DUO, Umbrella Microsoft Teams Phone, Direct Routing, Microsoft Teams Room Migrations from legacy phone systems to Cloud calling. E911 Configurations, Dial Plans, PSTN, Telephone Number Porting, Solution Architecture, SBC experience - Audiocodes, Acme Packets, CUBE Azure and Microsoft Teams Voice experience including design, implementation, and support. Python, JavaScript automation experience.
    vsuc_fltilesrefresh_TrophyIcon SIP
    Unity
    Cisco
    Cisco Unity Connection
    Microsoft Teams
    Cisco Router
    Session Initiation Protocol
    Cisco CallManager
    Cisco Certified Internetwork Expert
    VoIP Administration
  • $50 hourly

    • 5.0/5
    • (161 jobs)
    With over 20 years of experience in planning, installing, configuring, and debugging VoIP systems, I am confident that I can contribute significantly to your project. I have a proven track record in setting up and maintaining VoIP systems, including Kamailio, Asterisk, FreeSWITCH, FreePBX, VOS3000, A2Billing, ASTPP, 3CX, and Kazoo. Additionally, I have extensive experience working with SMS systems like PlaySMS, Jasmin, and Kannel. I am also 3CX certified, which further assures my capability to meet your VoIP needs with efficiency and precision. Whether it's troubleshooting, configuring systems, or managing complex installations, I bring a meticulous approach to ensure the project is delivered successfully and on time. If you choose to work with me, I guarantee 100% satisfaction and a solution tailored to your specific requirements.
    vsuc_fltilesrefresh_TrophyIcon SIP
    VoIP
    Asterisk
    VoIP Administration
    Twilio API
    MySQL Programming
    Session Initiation Protocol
    SMS Gateway
    Database Optimization
    Network Engineering
    FreePBX
    3CX
    Linux System Administration
    FreeSWITCH
  • $75 hourly

    • 5.0/5
    • (17 jobs)
    ✅ Microsoft Teams, Telephony and Teams integrated Contact Centers (Luware Nimbus) ✅ M365 service design, migration ✅ Intune ✅ Defender ✅ Azure, Azure AD ✅ Powershell ✅ Terraform ✅ IT Networks, DNS, Certificates ✅ VoIP gateways (AudioCodes, Sonus/Ribbon SBCs) ✅ Skype for Business ✅ Exchange ✅ Active Directory, ADFS Certifications • MCSE: Productivity Solutions Expert • MCSA: O365 • ITILv3 Foundation • Microsoft 365 certified: Teams Administrator Associate (MS-700) • Microsoft 365 Certified: Teams Voice Engineer Expert (MS-720) • Microsoft 365 Certified: Collaboration Communications Systems Engineer Associate (MS-721) I'm a seasoned IT Consultant with 10+ years of professional experience in the IT industry. Acting as an IT partner, providing expert guidance and support in various areas of information technology, including Microsoft 365, Azure, Networks, IT Infrastructure, Teams Telephony, Project Management, IT Infrastructure, Endpoint management and Security. Key responsibilites: Consultation Solution Design and Implementation Technical Support and Troubleshooting Security and Data Protection Training and Documentation Vendor Management Stakeholders Management Project reporting
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    Microsoft Endpoint Manager
    Microsoft Office
    IT Project Management
    Microsoft Teams
    VoIP Administration
    Skype For Business
    Project Engineering
    Microsoft Exchange Online
    Computer Network
    Office 365
    Microsoft Windows PowerShell
    DNS
    Microsoft Exchange Server
    Windows Server
    Microsoft Active Directory
  • $30 hourly

    • 4.9/5
    • (59 jobs)
    I am here with 13+ years of high experience specialized in creating applications from scratch and improvising the existing applications placing my feet parallel to present-era technologies. Innovation and hard work are my forte. I work to craft the best Android, iOS and Web applications for my clients. Web Technologies I am working on: Frontend: NextJS, ReactJS, MUI, AngularJS, VueJS, Typescript, Javascript, Bootstrap, HTML, CSS. Backend: NodeJS, Laravel, PHP. Databases: MySQL, MongoDB, Redis, Firestore Payment Gateways: Stripe, Paypal, Braintree I also have expertise in developing Cutting Edge WebRTC Video Conferencing for Web and Mobile Apps. WebRTC Technologies I have expertise in: - MediaSoup - Jitsi - XMPP - Twilio - Ejabberd - Erlang 3rd party APIs integration I have done includes: - Firebase - Facebook API - Foodics API - KVK (Chamber of Commerce) - Flight tracking API - Google APIs. - Adobe API
    vsuc_fltilesrefresh_TrophyIcon SIP
    Session Initiation Protocol
    Erlang
    XMPP
    WebRTC
    Objective-C
    Swift
    Android
    iOS Development
  • $50 hourly

    • 5.0/5
    • (18 jobs)
    I am a VoIP professional with over 12 years of experience. I am an expert in Asterisk, Freeswitch, SIP Trunking and provide consultations on these to my clients. Throughout my experience I have designed and developed a number of VoIP, Telecom Solutions like IVR Systems, Autodialers, Conferencing Solutions and Voice Mail solutions from scratch. I develop solutions over multiple programming languages like Javascript (NodeJS), PHP, Java using Asterisk (ARI, AMI and AGI) and Freeswitch (ESL). I also provide support for installation, configuration and maintenance of Asterisk, Freeswitch and other VoIP Switches.
    vsuc_fltilesrefresh_TrophyIcon SIP
    WebRTC
    FreeSWITCH
    Session Initiation Protocol
    Kamailio
    VoIP Software
    Asterisk
    Linux System Administration
    JavaScript
    Node.js
    VoIP Administration
    Twilio API
    PHP
    Web Service
  • $50 hourly

    • 4.9/5
    • (60 jobs)
    Telecom Software and Network Engineer more than 11th years in companies - communication providers. Main skills is design and deploying a complete infrastructure of voip provider, using OpenSource telephony technologies such as Freeswitch, Kamailio \ OpenSIPS, asterisk, etc. Mostly I'm dealing with emerging startups or with accomplished voip companies which want to improve\reorganize their infrastructure; create something new or fix some issue on their network. So it is main area but sure I can help with other projects that correspond to my list of skills.
    vsuc_fltilesrefresh_TrophyIcon SIP
    VoIP Software
    VoIP PBX
    VoIP Administration
    Erlang
    Apache CouchDB
    RabbitMQ
    Lua
    PostgreSQL
    MySQL
    OpenSIPS
    Kamailio
    FreeSWITCH
    VoIP
  • $60 hourly

    • 4.8/5
    • (26 jobs)
    Support and development on asterisk, vicidial, goautodial, fusionpbx, freeswitch Linux System Administration ( CentOS, Debian, Ubunut) Database Management (Mysql, PostgreSQL) Network Administration (Router, Switch, Hardware Firewall)
    vsuc_fltilesrefresh_TrophyIcon SIP
    VoIP
    Linux System Administration
    VICIDIAL
    PHP
    MySQL
    FreePBX
    Network Administration
    Android
    A2Billing
    iOS
    FreeSWITCH
    Asterisk
    Customer Relationship Management
    Mobile App
    Session Initiation Protocol
  • $75 hourly

    • 4.9/5
    • (31 jobs)
    I have been in the IT field for 12+ years. I have engineered, implemented and managed phones systems for most of the 10 years. I have dealt with most phone systems in my 10 year career. I also have a background in Networking. I am proficient in setting up LAN networks and basic routing. I also have dealt with a CLEC switch for part of my career. Vendors I worked with directly: Metaswitch Digium Adtran Edgewater Networks dba Ribbon Every major carrier in my area(ATT, Windstream, Frontier, Century Link) Fonality dba Netfortis Polycom Yealink Snom Interactive Intelligence dba Genesys GSuite Google Workspace Fusion PBX/FreePBX/FreeSwitch AWS Azure Cisco Networking Equipment Watchguard Sonicwall 3cx Hubspot SIP trunking with multiple VOIP providers
    vsuc_fltilesrefresh_TrophyIcon SIP
    Network Engineering
    Phone Communication
    Web Hosting
    VoIP
    FreePBX
    3CX
    Squarespace
    Telecommunications Engineering
    VoIP Administration
    Cisco IOS
    Asterisk
    Session Initiation Protocol
    Cisco Router
    Linux
  • $65 hourly

    • 5.0/5
    • (53 jobs)
    Hi, I'm an experienced and certified (MS700-MS720-MS721) Microsoft Teams Phone & Rooms engineer. I'm implementing, configuring and troubleshooting Microsoft Teams Phone & Rooms ecosystems for multinationals,SME's, nonprofit and government organizations. * Microsoft Teams Calling setup (Auto-attendants & Call Queues) * Microsoft Teams Direct Routing with Audiocodes SBC * Microsoft Teams Direct Routing with Hosted Audiocodes SBC * Microsoft Teams Calling Plans & Operator connect * Luware Nimbus routing and contact center solutions on Microsoft Teams * Roger365 contact center solutions on Microsoft Teams * Skype For Business on-premise to Microsoft Teams migrations * Teams devices and Teams Rooms systems
    vsuc_fltilesrefresh_TrophyIcon SIP
    Session Initiation Protocol
    Phone Communication
    VoIP Administration
    Microsoft Power Automate
    Mitel
    VoIP
    VoIP Software
    Skype For Business
    Microsoft Teams
    PBX
    Skype
    Call Center Management
    Office 365
  • $50 hourly

    • 4.8/5
    • (55 jobs)
    Good Day I'm Daniel Krahenbuhl. Originally from Switzerland and living in Gdańsk Poland for the last couple of years. I can communicate in English, german and french (if needed :-)). I do enjoy working as a freelance software engineer and sometimes project manager (if the project is interesting). It would be awesome to connect with you and hear what cool projects you have in mind. Let's do it and happy days always. My general work experience: I design and write Software over the last 30 years Node.JS backend development Build API’s / Integrate third party API’s Experience in MySQL/MariaDB, MongoDB Voice/Video/Asterisk: I work with Asterisk since its; s beginnings (25 years ago)
Especially if you build large, scalable services. 
| designed some of the largest and most complex Asterisk system globally. During the years i also gained a lot of in-dept knowledge of Twilio, Pipedrive and Hubspot. Third party API Integrations I have a lot experience in integrating and using following API's Hubspot, Pipedrive, Insightly, Sendgrid, MailChimp, and many more Monday.com Over 7 years of expertise in transforming businesses through cutting-edge process optimization and seamless integrations. With 30 years of programming experience and a background in business consulting, I possess a unique set of skills to elevate your organization to new heights. At the core of my services lies Monday.com, a powerful platform that has revolutionized how businesses manage their workflows and projects. As a seasoned Monday.com specialist, I am adept at tailoring this robust tool to suit your specific needs, streamlining your processes, and enhancing collaboration across your entire team.
    vsuc_fltilesrefresh_TrophyIcon SIP
    VoIP
    Twilio API
    RESTful API
    Node.js
    API Development
    Asterisk
    Pipedrive
    API Integration
    WebRTC
    FreePBX
    HubSpot
    Stripe API
    Nagios Core
    API
    PHP
  • $50 hourly

    • 4.8/5
    • (17 jobs)
    I'm a senior C, C++ developer with a passion for working on complex high-performance, and low­ latency systems for telecommunications like own Media Server to Media and Signaling servers like Freeswitch, Kamailio, OpenSIPS, JANUS, Kuranto, and JITSI. Furthermore, I started working on AI in the last six years and worked on ChatBots and VoiceBots. - Have a perfect experience on NLP/NLU open source and cloud platforms like Google dialog flow and Microsoft Luis. - Create custom Modules of Freesiwtch and JANUS for Google, Amazon, IBM Speech To Text, and Text to Speech for real-time transcribers. - Create Conversational IVR and Voice Translator with the help of Google And Amazon. - Real-Time text-to-speech and speech-to-text with NLP/NLU. - Real-Time translator using Google. - good experience in Server Side audio processing and sending audio to any channel. - Excellent experience on Kaldi, Rasa(NLP, NLU), and Python Wavenet library to train models. ✅ Technical Skills : - Development: C/C++, Python - Opensource: TensorFlow, Rasa, WebRTC, reSIProcate - Technology: SIP, Audio/Video, NLP, NLU, Kaldi, deep speech(Mozilla). - Tools (Master): Wireshark, SIPp - Having enough experience with VoIP library for iOS, Android & Windows in C, and C++. - Having experience in VoIP clients and server development. ✅ Develop for all the platforms you need. We cover: - Web - iOS and Android phones and tablets Develop web apps that work on mobile browsers, e.g., video chats, audio and video calling, and audio-video SDK. We help to plan your product and develop it so that users love it. Work with companies and startups to create new products and improve existing ones. ✅ Have the right processes you know in advance. Ours: 1 - Sales managers are 1st level, software analysts. They clarify your needs. You get 3 results: what users can do - user stories, recommended technologies, and estimate based on previous projects. 2 - Analysts clarify details and draw wireframes. They are mockups of all the pages with clickable buttons. So you can play with your app before it’s developed and make changes for cheap. Based on wireframes, we calculate project time and price estimation. 3 - Designers draw clickable graphic design prototypes. 4 - A team of developers, test engineers, and a project manager develops the product. 5 - The team installs it on your server and helps with app store submission. We do maintenance - part-time work on minor improvements after launch. Write to discuss and estimate your project. We give user stories and recommend technologies for free after a call. Without a call, we can’t do it well, unfortunately. All the right questions in writing would have taken days and still much missed. Answer the same workday. On weekends we rest, but if you have a chance - respond too. So please write to us now :)
    vsuc_fltilesrefresh_TrophyIcon SIP
    React Native
    Session Initiation Protocol
    LLM Prompt Engineering
    LLM Prompt
    Bot Development
    VoIP
    WebRTC
    Kamailio
    OpenSIPS
    FreeSWITCH
    Video Stream
    Swift
    Dialogflow
    Artificial Intelligence
    Node.js
    Kotlin
    C++
  • $200 hourly

    • 5.0/5
    • (227 jobs)
    With over two decades of extensive experience in the world of programming, I've honed a knack for efficiency and innovation. I believe in optimizing time and delivering solutions that matter, constantly pushing the boundaries of what’s possible. From the age of 10, programming hasn't just been a job—it's been a calling. Whether you're looking for new project development or leveraging existing solutions, I’m your go-to expert. Experience: Twenty-two years of diverse commercial programming experience and 31+ years overall programming —from Linux administration and virtualization to end-user web development and complex billing systems for VoIP. Expert work with Asterisk since its inception and substantial experience with FreePBX, Trixbox, and a2billing. Proudly, I'm one of the contributing minds behind a2billing.org's trunk. My depth of expertise encompasses database administration and architecture, especially with MySQL and Postgres. Education: Master of Science in Computer Science (confirmed by WES) Technical Skills & Specializations: Languages: Python/Django, Javascript/jQuery, SQL, PHP, C/C++, Perl, Prolog/Lisp, and Forth. Platforms & Tools: Asterisk, Opensips, Kamailio, Callweaver (faxing). Noteworthy Contributions: Developed modules for FreePBX, Elastix, Trixbox, and a2billing. Philosophy: I stand for originality and meaningful impact. If a task doesn’t need to be done, I won’t push for it. Instead, I'll direct my energy towards novel and intriguing challenges, ensuring that you get the best of both worlds—innovation and efficiency.
    vsuc_fltilesrefresh_TrophyIcon SIP
    Session Initiation Protocol
    C++
    PHP
    Kamailio
    Asterisk
    MySQL
    Amazon EC2
    Linux System Administration
    SQL
    Elastix
    A2Billing
    VoIP Administration
    OpenSIPS
    FreePBX
    Virtualization
    Python
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