Cisco's Extended Erlang B example assumes that 50 percent of blocked users retry immediately. Extended Erlang B is Erlang B with blocked calls retried instead of lost.

Checked 2026-09-25

Vendor
Cisco
Product
Cisco IOS VoIP solutions
Subsystem
trunk and port sizing
Deployment
on-premises
Region
not restricted
Release range
document updated 2001-07-02
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-extended-erlang-b-retry-example. WarmTransfer. https://warmtransfer.net/knowledge/claims/erlang-traffic-engineering-extended-erlang-b-retry-example

BibTeX

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

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