Grade of service (percent blockage) is the probability that a resource is busy during the busy hour so that a call is lost or blocked; a grade of service of 0.01 means 1% of busy-hour calls are blocked.

Checked 2026-09-25

Vendor
Cisco
Product
Unified Contact Center Enterprise
Subsystem
trunk and port sizing
Deployment
on-premises
Region
not restricted
Release range
15.0(1)
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Erlang B and Erlang C for voice and contact center sizing: source note erlang-traffic-engineering-gos-definition. WarmTransfer. https://warmtransfer.net/knowledge/claims/erlang-traffic-engineering-gos-definition

BibTeX

@misc{warmtransfer-claim-erlang-traffic-engineering-gos-definition,
  title  = {Erlang B and Erlang C for voice and contact center sizing: source note erlang-traffic-engineering-gos-definition},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/erlang-traffic-engineering-gos-definition},
  note   = {Source note erlang-traffic-engineering-gos-definition, checked 2026-09-25}
}

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