NWG/RFC# 717 JBP 30-JUN-76 16:58 35873
Assigned Network Numbers
Network Working Group Jon Postel
Request for Comments 717 SRI-ARC
NIC 35873 1 July 1976
Assigned Network Numbers
This note specifies the numbers assigned to identify networks for use in
the inter-network protocol experiments. Additional Numbers are assigned
by Jon Postel [POSTEL@ISIC or (415) 326-6200 x3718].
Assigned Network Numbers
Name Decimal Octal
---------- ------- -----
BBNRCCnet 3 3
SanFranPRnet 7 7
ARPANET 10 12
BostonPRnet 11 13
Internetwork Header Format
For convenience the current Internetwork protocol header and TCP
headers are reproduced here:
Octet Bit Use (Width)
--- Beginning of protocol-independent information ---
0 Destination net (8)
1-3 Destination host (24)
4 Source net (8)
5-7 Source host (24)
8-9 Data length in octets (16)
10 Header length in octets (8)
11 0-3 Format (4)
This field selects the appropriate gateway processing and is used
to dispatch the packet to the appropriate protocol module in the
destination. The following values are defined for this field:
0 -- Escape; protocol is specified by a subsequent field
1 -- TCP
2 -- Secure TCP
3-16 -- Not allocated
17 -- Cross internet debugging
--- End of protocol-independent information
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NWG/RFC# 717 JBP 30-JUN-76 16:58 35873
Assigned Network Numbers
--- Beginning of TCP specific information ---
11 4-7 Protocol version (4)
12-15 Sequence number (32)
16-17 Window (16)
18-20 Control (as before) (24)
21-23 Destination port (24)
24 Packet label for debugging(8)
25-27 Source port (24)
28-31 Acknowledgement number (32)
32-33 Checksum (16)
34- Data
--- End of TCP specific information ---
--- Beginning of short TCP specific information ---
11 4-7 Protocol Version (4)
12-25 Sequence number (32)
16 Destination KID (8)
17 Source KID (8)
18-19 Control (no special function field)(16)
20- Data
--- End of short TCP specific information ---
2
RFC, FYI, BCP