GRUU

1
GRUU

• Jonathan Rosenberg
• Cisco Systems

2
Main Changes

• Up front discussion of URI properties
• Opaque URI parameter for constructing GRUU
• Procedure for EP to remove itself from RR if UA
  supports GRUU
• REGISTER response has Require
• New GRUU construction algorithms using opaque
• Mechanism for picking gruu in dialog forming
  req/res

• Grammar bug missing lt and gt for instance
• Registrar doesnt delete two registrations with
  same instance just uses most recent
• Inline with sip-outbound
• Text on administratively constructed gruu in
  servers really easy
• More detailed discussion on service treatment
  property for GRUU
• 404 vs. 480 responses clarified

3
Issue 1 Extraction of AOR from GRUU

• Currently, opaque parameter contains blob, remove
  it, you get the AOR
• sipuser_at_domainopaquegruu-blob
• sipuser_at_domain
• Have gotten a few complaints about this
• One suggestion to leave this to another spec
• Suggestion on listsipAlice_at_baropaque-aorfalse
  gruu-id"lturnuuid...gt
• Another suggestionsipgruu-blobs_at_example.comaor
  user_at_example.com

• Do we want to change this?
• PROPOSAL NO

4
Issue 2 The double role of GRUU

• We are using GRUU in two ways
• As a target for mid-dialog requests (consequence
  of its inclusion in Contact)
• As a target for new requests to that UA
• But there are differences
• Service Treatment
• Would like service treatment for new requests
• Probably not for mid-dialog
• Record-routing and GRUU interactions only for
  mid-dialog requests

• Idea 1 GRUU only for new requests
• Original design worked this way carried in a
  Gruu header field in INVITE request or response,
  but had backwards compatibility problem
• Lose significant GRUU benefit of moving dialogs
  when a UA re-registers mid-dialog
• Idea 2 Endpoints record-route
• Use their IP-address in there
• Means Contact is ignored for mid-dialog requests
• Fundamental change in SIP usage
• Proposal Stay as is