Bulletins from the Pacific Packet Radio Society - page 011

11. Maybe a repeater should implement "Please-repeat-me/don't-repeat-me" status bits for each user address available. Users should be able to selectively address or access each machine or network server. A "please- repeat-me" directed to one machine should be interpreted as "don't repeat-me" by other machines. For broadcast protocol purposes (round-tables, nets, etc.) one may wish to say "Will-everybody-please-repeat-me".

12. Repeaters will send "Repeater-ON" status message and current routing information to other repeaters in the network. Repeater beacon messages inform users what machines are operational and their addresses.

13. Hop-by-hop error checking would provide satisfactory reliability for the proposed datagram implementation.

14. Static assignment of HDLC addresses would be ok for permanent stations like repeaters or other network servers.

15. No static assignment of addresses implies:
a.) Dynamic assignment is required -or-
b.) Use of IP headers is required everywhere

16. Dynamic assignment of addresses implies:
a.) All servers covering one area are coordinated and don't assign the same address to different users.
b.) Deassignment of addresses must be foolproof and implemented through user-initiated commands or through timeouts. No conditions should permit an address to "lock-up" to a non- existent or inactive station.
c.) An Address needs to be defined for users who don't have an address to ask for an address. Probably 00 or FF, with FF most likely.

17. Use of IP headers implies:
a. ) More overhead per packet approx. 30-40 bytes.
b.) Only one HDLC address code is required for all users.
c.) From and To callsigns will be in each packet.
d.) From and To network node address will be in each packet.
e.) Other useful info in header, such as protocol type field.
f.) More overhead on the software, which will be receiving, storing, and checking packets not destined for its station.

18. Some block of HDLC addresses should be reserved for network usage and servers. Here is one proposal for assignments:

00 Maintenance or NOP address
01-7F Direct connect for stations not using IP protocol headers

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