1NSIP(4) Kernel Interfaces Manual NSIP(4)
2
6 nsip - software network interface encapsulating ns packets in ip pack‐
7 ets.
8
10 #include <netns/ns_if.h>
11 Not currently supported under 2.11BSD
13
15 The nsip interface is a software mechanism which may be used to trans‐
16 mit Xerox NS(tm) packets through otherwise uncooperative networks. It
17 functions by prepending an IP header, and resubmitting the packet
18 through the unix IP machinery.
19 The super-user can advise the operating system of a willing partner by
21 naming an IP address to be associated with an NS address. Presently,
22 only specific hosts pairs are allowed, and for each host pair, an arti‐
23 ficial point-to-point interface is constructed. At some future date,
24 IP broadcast addresses or hosts may be paired with NS networks or
25 hosts.
26 Specifically, a socket option of SO_NSIP_ROUTE is set on a socket of
28 family AF_NS, type SOCK_DGRAM, passing the following structure:
29 struct nsip_req {
31 struct sockaddr rq_ns; /* must be ns format destination */
32 struct sockaddr rq_ip; /* must be ip format gateway */
33 short rq_flags;
34 };
35
38 nsip%d: can't handle af%d. The interface was handed a message with
39 addresses formatted in an unsuitable address family; the packet was
40 dropped.
41
43 intro(4N), ns(4F)
44
46 It is absurd to have a separate pseudo-device for each pt-to-pt link.
47 There is no way to change the IP address for an NS host once the the
48 encapsulation interface is set up. The request should honor flags of
49 RTF_GATEWAY to indicate remote networks, and the absence of RTF_UP
50 should be a clue to remove that partner. This was intended to postpone
51 the necessity of rewriting reverse ARP for the en device, and to allow
52 passing XNS packets through an Arpanet-Milnet gateway, to facilitate
53 testing between some co-operating universities.
543rd Berkeley Distribution January 27, 1996 NSIP(4)