ITU-T Recommendation E.521 (11/88), in force, covers calculating the number of circuits in a group that carries overflow traffic.

Checked 2026-09-25

Vendor
vendor-neutral
Product
not restricted
Subsystem
trunk and port sizing
Deployment
carrier-network
Region
not restricted
Release range
E.521 (11/88)
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-itu-e521-overflow. WarmTransfer. https://warmtransfer.net/knowledge/claims/erlang-traffic-engineering-itu-e521-overflow

BibTeX

@misc{warmtransfer-claim-erlang-traffic-engineering-itu-e521-overflow,
  title  = {Erlang B and Erlang C for voice and contact center sizing: source note erlang-traffic-engineering-itu-e521-overflow},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/erlang-traffic-engineering-itu-e521-overflow},
  note   = {Source note erlang-traffic-engineering-itu-e521-overflow, checked 2026-09-25}
}

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