RSVP

1. Resource reservation protocol (RSVP)
2. Mediatrace

Resource reservation protocol (RSVP)

• unicast messages per hop towards destination
  • if intermediate devices do not support, they just forward
• messages:
  • Path
  • Resv
  • ResvConf
• IntServ model
• WFQ
  • processes all traffic by default
• application ID
  • RFC 2872
  • object, ASCII-string (policy-locator): mapping session to app
    • CUCM: AudioStream, VideoStream
• IP option: Router Alert

(config)# ip rsvp policy identity <POLICY> policy-locator <WILDCARD>

; does not account for L2 overhead
(config-if)# ip rsvp bandwidth <kbps> [<max_flow_kbps>]

(config-if)# max-reserved-bandwidth <kbps>

; DSCP for RSVP control messages
(config-if)# ip rsvp signalling dscp <N>

; use CBWFQ + LLQ instead of RSVP
(config-if)# ip rsvp resource-provider none

; disable processing all traffic by RSVP, DiffServ instead of IntServ
(config-if)# ip rsvp data-packet classification none

(config-if)# ip rsvp policy local identity <POLICY>

; RSVP message types
(config-rsvp-local-if-policy)# forward all
(config-rsvp-local-if-policy)# maximum bandwidth group <kbps>

Mediatrace

• traceroute with per-hop information
• detects retagging (≡ QoS loss), drops, congestion
• uses RSVP for transport, no reservation or admission control
• TTL = 255
• unicast RSVP ⇒ nodes without RSVP just forward packets

; implicitly enabled RSVP
(config)# mediatrace responder
(config)# mediatrace initiator source-int <INTF>

# mediatrace poll path source <IP> destination <IP> perf-mon