1. IETF 55 (November 2002, Atlanta)
RFC 2806bis: tel URI
Henning Schulzrinne
Columbia University
IPTEL working group
IETF 55 (November 2002, Atlanta)

2. Status - 06 Changes: technically, seems to have converged  WGLC?
URI comparisons CI, but use lower-case parameters
BNF clean-up: component names, avoid parameter ordering constraints
recommended parameter ordering
technically, seems to have converged  WGLC?
may need editorial clean-up

3. Open issue: context currently, two approaches:
DNS: tel:7042;phone-context=cs.columbia.edu
prefix: tel: ;phone-context=
many choices for context
do we need to recommend one 
lowest number in range  longer than necessary in most cases
smallest prefix  not always unique if not divided by digit
or prefix list: ;phone-context=+31,+49
is this useful?
e.g., European 0800 numbers?

4. Open issue: global numbers
Global numbers are tel:+CC-something
unlike local numbers, require no context
freephone (“800”) numbers are perceived as global, but are local
regardless of what spec will say, people will write tel:

5. Draft progression Planned for Draft Standard
Need interoperability matrix
;context implementations?