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RFC 637 UNKNOWN INFRASTRUCTURE · ROUTING

Change of network address for SU-DSL

SU-DSL's network address moves from 130 to 194

On rfc-editor.org ↗
PUBLISHED
April 1974
AUTHORS
A.M. McKenzie
STREAM
Legacy
OLD NETWORK ADDRESS
130
NEW NETWORK ADDRESS
194
IMP LOCATION
2
OLD HOST POSITION
2
NEW HOST POSITION
3
DOI
10.17487/RFC0637

RFC text

Original text · RFC Editor View on rfc-editor.org ↗ 
Network Working Group                                   Alex A. McKenzie
RFC # 637                                               BBN-NET
NIC # 30519                                             April 23, 1974


                  CHANGE OF NETWORK ADDRESS FOR SU-DSL

Effective immediately, the Host at Stanford Electronics Research Lab.
(SU-DSL), a Very Distant Host connected to the SRI IMP, has its address
changed from IMP 2, Host 2, to IMP 2 Host 3.  Thus its "Network Address"
is changed from 130 to 194.

Host 2 on IMP 2 will eventually be a PDP-11 operated by the SRI
Artificial Intelligence Center.










       [ This RFC was put into machine readable form for entry ]
       [ into the online RFC archives by Alex McKenzie with    ]
       [ support from GTE, formerly BBN Corp.            10/99 ]

AI ELI5

On this page
PROBLEMThe Stanford Electronics Research Lab very distant host needs to be reassigned from host 2 to host 3 on the same IMP, requiring an address update.
MECHANISMThe host location on IMP 2 changes from position 2 to position 3. The network address recalculation reflects this: from 130 to 194.
ADDRESS UPDATED IMMEDIATELYThe address change is effective immediately and users and routing systems must be notified of the new network address.

§1Address Reassignment

RFC 637 announces an immediate change to the network address of the Stanford Electronics Research Lab (SU-DSL) very distant host. The host was at IMP 2, Host 2, with network address 130. It is now at IMP 2, Host 3, with network address 194. Unlike RFC 634, which announced a move to a different IMP location, this change is within the same IMP facility at Stanford Research Institute (SRI).

The previous host position 2 on IMP 2 will be assigned to a PDP-11 operated by the SRI Artificial Intelligence Center, so the reassignment makes room for that new system.

A computer's address changed because it switched positions on the same network box, making room for a new computer to use the old spot.

§2Within-IMP Reassignment

This address change differs from typical host migrations in that the IMP location remains the same. The SU-DSL host stays on IMP 2 (the SRI connection point) but moves from host slot 2 to host slot 3. The network address reflects this shift: 130 to 194 encodes the new position. Such within-IMP reassignments are common in network management when hosts need to be repositioned or when different organizations at the same site need to connect to different host positions.

Instead of moving to a different network box, this computer just switched slots on the same box, and a new computer takes its old slot.

§3Immediate Effect

The RFC emphasizes that the change is effective immediately—not pending or scheduled for a future date. This immediate effect suggests either that the SU-DSL host had not been connected before or that the change had already occurred physically and the RFC serves to officially announce it to the network community. The notice ensures that all network routing tables and host directories are updated without delay to reflect the new address.

The address changes right away, not later. All the network computers need to know the new address immediately.