Call Center and Contact Center Networks

April 15, 2026·3 min read·443 words

A call center or contact center network must support 50-1,000 simultaneous agents using high-quality VoIP (<150 ms latency), outbound video conferencing, omnichannel communications (voice + chat + email), and integrated CRM. Downtime causes catastrophic revenue losses. 2026 call center guide.

Requirements

Simultaneous agents: 50-1000
VoIP: <150 ms latency, <30 ms jitter, <1% packet loss
Omnichannel communications: voice + chat + email + SMS + WhatsApp Business
CRM integration: Salesforce, Zendesk, HubSpot
Recording of 100% of calls (PCI-DSS for card payments, GDPR)
Availability: 99.99% for critical customer support

Call center architecture

Telephony: Cisco UCM, Mitel MX-ONE, 3CX, Genesys Cloud, Avaya Aura
Core switching: Catalyst 9300 with PoE+ for IP phones and laptops
Firewall: FortiGate 100F/200F with SBC (Session Border Controller)
SIP trunking: 2 different operators (Orange Business, Colt, Voxbone)
Bandwidth: 100 Kbps per agent × 500 agents = 50 Mbps for voice only, plus video and data

IP phones

Cisco 8851/8861: enterprise benchmark
Yealink T54W, T57W: excellent value for money
Poly (formerly Polycom) VVX 450
Softphone with USB headset: increasingly common and reduces hardware requirements
Budget: €150-400 excluding tax per phone, or €50 for a USB headset

Voice QoS

Classification: DSCP EF (46) for RTP
Traffic marking at the IP phone (voice VLAN)
LLQ at the WAN edge
Policing: 100 Kbps per call (G.711) or 30 Kbps (G.722)
Pre-production testing: a MOS (Mean Opinion Score) >4.0 is mandatory

Omnichannel contact center

Genesys Cloud: market leader with a cloud-first approach
Amazon Connect: AWS cloud platform
Cisco Webex Contact Center: migration path from UCCX
NICE CXone: enterprise market leader
Talkdesk: innovative cloud platform

AI and automation

AI chatbots (ChatGPT, Azure Bot Service, IBM Watson)
Voice AI: Google Cloud Speech, Amazon Lex, and Otter transcription
Real-time sentiment analysis
AI-powered automatic routing based on skills and urgency
Automatically populated knowledge base

Call recording

Mandatory PCI-DSS compliance for card payments
Card payment data must be excluded during entry using automatic pause/resume
Storage: minimum of 1 year, or 7 years for disputes
Products: NICE NIM, Verint, CallCabinet (Teams)

Remote agents

Softphone and headset supplied to the agent
ZTNA for secure CRM access
MFA is mandatory
Home bandwidth: minimum upload speed of 10 Mbps for video and voice
Quality management: QM tools such as NICE

Budget for a 200-agent call center

IP phones and softphones: ~€40,000 excluding tax
Cisco UCM and office infrastructure: ~€80,000 excluding tax
Genesys Cloud licenses for 200 agents: ~€200,000 excluding tax/year
FortiGate SBC and SIP trunks: ~€15,000 excluding tax
Recording and QM: ~€100,000 excluding tax over 3 years
3-year total: ~€800,000 excluding tax

Order from OPTINOC

Turnkey call center infrastructure: Cisco UCM/Genesys + FortiGate SBC + IP phones. PCI-DSS expertise. Quote for 50-1000 agents within 48 hours.