Similar to HTTP_cookie

RC2

KOI8-U

RFC 2322

Real-Time Streaming Protocol

Virtual Router Redundancy Protocol

Mailto

IP Payload Compression Protocol

Uniform Resource Identifier

Data URI scheme

VCard

ICalendar

Differentiated services

Point-to-Point Protocol over Ethernet

Year 10,000 problem

Online Certificate Status Protocol

Internet Printing Protocol

Diffie–Hellman key exchange

S/MIME

Point-to-Point Tunneling Protocol

Layer 2 Tunneling Protocol

Simple public-key infrastructure

Multicast Listener Discovery

Common Open Policy Service

Media Gateway Control Protocol

H.248

Session Announcement Protocol

MISTY1

Sieve (mail filtering language)