Hire the Best VOIP Administrators
in Serbia

I'm network and VOIP engineer with 11 years of experience. Over time I've completed the following certificates: 1. CCNA 2. CCNA security 3. CCNA wireless 4. CCNP - Not certified yet 5. MTCNA 6. MTCRE 7. Linux Essentials 8. LPIC-1 9. Sophos UTM Engineer 10. dCAA 11. 3CX I have experience with the following vendors: Cisco Cisco ACI MikroTIK Sophos UTM Fortinet Checkpoint HP Ubiquiti - Unifi Juniper Alied Telesis PfSense I can help you with: Router configuration WAN Failover VPNs - IPSec, L2TP, OpenVPN etc... Routing - Static, Dynamic including OSPF and BGP MPLS - L3VPN IPSec Firewall - Filter rules, mangle rules etc... FHRP VRF QoS Switch configuration Vlans FHRP Etherchannel Port security Voice Vlan Trunks Troubleshooting Wireless configuration Cisco WLC and LWAPs Ubiquity Unifi - AP, Switch, USG MikroTIK - I have probably configured 500+ MikroTIK devices VOIP 3CX PBX deployment on prem and in cloud Phone management SIP Trunk management DID management IVR Queues Ring Groups etc... Email security Sophos UTM email filter Spam Titan email filter DNS - SPF, DKIM, DMARC Reach out if you find this interesting and we can discuss the details about your project.

My name is Djordje(George) Colic. I live in Serbia. I am windows and linux server system administrator. I have MCSA certificate. For 8 years I was working as system administrator for Mcs systems from San Diego and Miami Lakes IT . This is remote job. I heave experience in using ConnectWise and Ninja RMM as remote management tools. I am logging in to remote networks via ConnectWise or VPN- L2TP/IPsec or OpenVPN and then I use RDP to login to server or any workstation. I am giving support to customers via phone, ConnectWise , RDP or TeamViewer. This support includes their servers, workstations, printers , support with their dedicated applications , office 365. I am giving suport to VOIP customers. They have AT&T Synpase or SkyTalk phone system. Synapse Gateways are PSTN 67010 or SIP 67070. Routers: I was working with SonicWall , Peplink , Mikrotik routers . I am in charge for the maintenance of customer’s and office servers and workstations . For automation tasks I am using batch and powershell scripts. Server OS: Windows Server 2016 or 2012. Workstations: windows 10 or 7. Linux server OS: Red Hat . I am logging in to linux servers via SSH to do every day management tasks. Virtualization: VMWare , HyperV. Cloud: I have experience working in AWS . Every network is Domain network with Domain Controller. For file server we are using Synology NAS where important documents are kept on network share. I am also using NAS as VPN server to access remote network. I have knowledge of Java programming and power shell. As DevOPS engineer , I was working for Avi . Our client had Ping Directory , Ping Proxy servers . There were different environments. Server OS: Red Hat Enterprise Linux Server release 7.9 . I was logging into client network via SSH. I have experience in managing linux servers.

Technology projects rarely fail because of technology. They fail because priorities aren’t aligned, communication breaks down, risks aren’t managed early enough, or teams aren’t working toward the same goal. That’s where I come in. For the past 17+ years I’ve been helping technology companies build stronger delivery organizations, improve operations, lead cross-functional programs, and solve complex execution challenges. I’ve managed global teams across Europe, the UK, India, and North America, worked with Fortune 500 customers, and partnered closely with Product, Engineering, Customer Success, Professional Services, and executive leadership. Most of my work sits where technology meets business. Whether it’s leading a large implementation, improving delivery processes, building governance frameworks, scaling support and cloud operations, or helping teams adopt AI into their daily workflows, my focus is always the same: make execution simpler, more predictable, and easier to scale. I enjoy stepping into situations where there are too many moving parts, unclear ownership, or growing operational complexity. Bringing structure, aligning stakeholders, and helping teams deliver successfully is what I’ve spent my career doing. I can help with: • Technical Program & Project Management • PMO setup and delivery governance • Cross-functional program leadership • IT Operations & Cloud Operations • Service Delivery Management • Executive reporting & stakeholder management • Process improvement & operational excellence • AI workflow adoption and automation • Customer onboarding & implementation programs • Team leadership, coaching, and organizational scaling If you’re looking for someone who can keep projects moving, bring clarity to complex initiatives, and work comfortably with both engineers and executives, I’d be happy to discuss your project.

Skilled System Administrator and Network Engineer with over 20 years of hands-on experience, adept at organizing networks for single-office environments or multiple offices connected via VPN. I am highly proficient in Unix system administration (Linux and FreeBSD), covering DNS, DHCP, LAMP/LEMP, FTP, SMTP, SNMP, ACLs, firewalls, and NAT, BGP. My expertise also extends to major cloud platforms (AWS, Vultr, DigitalOcean) and virtualization technologies (vSphere, Hyper-V, Proxmox), as well as monitoring tools (Zabbix) and VoIP/IP telephony systems (Asterisk, FreePBX). Here is what past clients have said about my work: - “Pavel was fantastic! My project hit a snag and I needed an FTP server configured quickly. He jumped in immediately, resolved the issue in no time, and answered all my questions in a friendly manner. This guy is a real problem solver!” - “Very smart when it comes to Linux systems—was able to help with our issue.” - “A very skilled and professional expert who solved all additional and unexpected problems with patience. He overdelivered, and I 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.” I take pride in my ability to quickly diagnose issues, implement reliable solutions, and consistently exceed client expectations.

I have 35+ years experience in network projects including design, implementation, system administration and in software development. For the first 5 years of my career I worked on software development: coding and especially testing. For the last 30 years I'm working on implementation and maintenance of University of Nis WAN. Last 26 years I'm deeply involved in AMRES (Academic Network of Serbia) project. Don't fix it if it ain't broken, don't break it if you can't fix it! SKILLS SUMMARY - Any system administration tasks - Operating Systems: any *nix (Linux, FreeBSD, SGI IRIX, SCO, Solaris, OSX), Windows 3.1/9x/Me/XP/Vista/W7/W8/W10/W11, WinServer NT/2K/2003/2008/2012/2016 - LAN & WAN: Ethernet, Fast Ethernet, Gigabit Ethernet, FDDI and Wireless LANs. T1/T3, SDH/SONET, Frame Relay, WDM, ISDN, ADSL, SHDSL, Cable Modems, Cellular, X.25. - Network Protocols: TCP/IP, IPv6, UDP, OSI, CDP, IP Multicast, IPSec, VoIP, Routing, VLANs, Bridging, Trunking, VPN, SNA, DLS - Network Services & servers: SMTP/POP3/IMAP, FTP/SFTP, Telnet/SSH, HTTP/HTTPS, DNS, DHCP, NNTP, NTP, LDAP, SNMP, NETBIOS, Apache, Nginx, MySQL, Plesk, cPanel, Zimbra, VMware, CentOS, Ubuntu, Debian - Network Equipment: various types of modems, firewalls, switches and routers. - Dedicated, VPS and cloud environment servers (Amazon AWS, Google Cloud, MS Azure, Digital Ocean, Linode). - Programming Languages: Unix Shell scripting, BASH, C, Pascal, MS Visual Basic, PHP, HTML, (a bit of Python).

Expert DevOps and Full Stack Engineer with More than 6 years of experience as a Cloud Architect. DevOps expert with a focus on deploying cost effective microservices based solutions in the cloud and local machines ,that can meet the demands of your application while being able to scale. My ability to not only deliver on solutions but also interact like a pro in customer facing situations, makes me an ideal part of any clients team. Whether you need to migrate your workloads to the cloud, optimize your application, well-architect highly-available cloud infrastructure, or automate pipelines and deployments, I have the experience and expertise to help. With most of my projects, I am responsible for everything from ground up. This, of course, includes the development lifecycle, automated release pipelines, automated deployments, version control, and Infrastructure-as-Code. I have vast experience with designing and developing system architectures in Amazon Web Services, Microsoft Azure, and Google Cloud. Have knowledge of technologies which include Docker, Kubernetes, ECS, Azure, Jenkins, Elasticsearch, RDS Aurora, and Terraform, Cloudformation, I am also experienced in Azure devops , Codepipeline, Codebuild, and Ansible.