The Erlang-A queue (M/M/c+M) adds exponential customer abandonment at rate theta to the M/M/c model; with theta set to zero it becomes the Erlang-C queue.

Checked 2026-09-25

when one sets the abandonment parameter θ=0, we shut off the abandonment process and we obtain the Erlang-C queue
Vendor
vendor-neutral
Product
not restricted
Subsystem
agent staffing
Deployment
any
Region
not restricted
Release range
arXiv v1 2023-08-09
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-erlang-a-reduces-to-c. WarmTransfer. https://warmtransfer.net/knowledge/claims/erlang-traffic-engineering-erlang-a-reduces-to-c

BibTeX

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

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