proxy server
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... user agents, and intermediate elements are known as proxy servers. A
typical SIP configuration, referred to as the SIP ...
... prevent such attacks. Clients are simply dependent on proxy servers
for call completion, and must trust that they implement the protocol
...
... traffic (in the absence of
DNSSEC), whereas compromising and commandeering a proxy server
requires a break-in, and is seen as the considerably less likely
downgrade threat.
...