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RFC1700 - часть 142


"n", "h' "l", and "i". Thus, a host table address may be represented

as: "n.h.l.i". Each of these four numbers will have either one, two,

or three decimal digits and will never have a value greater than 255.

For example, in the host table, address: "10.2.0.124", n=10, h=2, l=0,

and i=124. To convert a host table address to a MILNET X.25 address:

1. If h < 64, the host table address corresponds to the X.25

physical address:

ZZZZ F IIIHHZZ (SS)

where:

ZZZZ = 0000 as required

F = 0 because the address is a physical address;

III is a three decimal digit respresentation of

"i", right-adjusted and padded with leading

Reynolds & Postel [Page 187]

RFC 1700 Assigned Numbers October 1994

zeros if required;

HH is a two decimal digit representation of "h",

right-adjusted and padded with leading zeros

if required;

ZZ = 00 and

(SS) is optional

In the example given above, the host table address 10.2.0.124

corresponds to the X.25 physical address 000001240200.

2. If h > 64 or h = 64, the host table address corresponds to the

X.25 logical address

ZZZZ F RRRRRZZ (SS)

where:

ZZZZ = 0000 as required

F = 1 because the address is a logical address;

RRRRR is a five decimal digit representation of

the result "r" of the calculation

r = h * 256 + i

(Note that the decimal representation of

"r" will always require five digits);

ZZ = 00 and

(SS) is optional

Thus, the host table address 10.83.0.207 corresponds to the X.25

logical address 000012145500.

In both cases, the "n" and "l" fields of the host table address are

not used.

REFERENCES

[BBN1822] BBN, "Specifications for the Interconnection of a Host and

Reynolds & Postel [Page 188]

RFC 1700 Assigned Numbers October 1994

an IMP", Report 1822, Bolt Beranek and Newman, Cambridge,

Massachusetts, revised, December 1981.

[ETHERNET] "The Ethernet, A Local Area Network: Data Link Layer and




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