**** Footnote: 0***
Some of these protocols, particularly those dated April 1, can be described as impractical at best. For instance, RFC 1149 (dated 1990 April 1) describes the transmission of IP datagrams by carrier pigeon and RFC 1437 (dated 1993 April 1) describes the transmission of people by electronic mail.
**** Footnote: 1***
Prior to 1993, the NIC function was performed by the DDN NIC (nic.ddn.mil). See RFC 1400 for more information about this transition.
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Older implementations, such as TCP/IP for MVS prior to Version 3 Release 1 and TCP/IP for VM prior to Version 2 Release 3 used as the loopback address. Where an implementation supports both, such as the current MVS and VM versions, is to be preferred to
**** Footnote: 3***
In IPv6 (see IP Version 6 (IPv6)) IGMP is integrated into ICMP, since all IPv6 hosts will be required to support multicasting. In IPv4, multicasting support is optional so, unlike IP and ICMP, IGMP is not required.
**** Footnote: 4***
In general, the distance will be measured in hops, but strictly speaking the TTL value is, as always, ``the time in seconds, with each hop being a minimum of one second''.
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The ATM Forum is a worldwide organization, aimed at promoting ATM within the industry and the end-user community. The membership includes more than 500 companies representing all sectors of the communications and computer industries as well as a number of government agencies, research organizations and users.
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Internet-Drafts may be obtained using anonymous FTP from directory Internet-Drafts from a number of sites, including ds.internic.net. The status of draft documents can be found in the file 1id-abstracts.txt in the same directory.
**** Footnote: 7***
Topologically, header translators, or other IPv6-capable routers, connected to multiple IPv6-complete areas have the effect of combining these areas into a single IPv6-complete area. The same applies to IPv4-complete areas as well.
**** Footnote: 8***
Daemon, pronounced ``demon'', is a UNIX term for a background server process. Usually, daemons have names ending with a ``d''. An analogous concept for MVS is a server running in a separate address space from TCP/IP, for VM it is a separate service virtual machine, for OS/2 it is a separate OS/2 session, and so on. Although TCP/IP servers are often implemented differently on different platforms, the routed daemon is implemented like this on each of these platforms.
**** Footnote: 9***
This keepalive message is implemented in the application layer, and is independent of the keepalive message available in many TCP implementations.
**** Footnote: 10***
RFC 1267 uses uppercase to name BGP messages, so we shall do the same in this section.
**** Footnote: 11***
At the time of writing there were nine root servers. The current list is available by anonymous FTP from ftp.rs.internic.net in the file netinfo/root-servers.txt
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VM also supports as a loopback address for compatibility with older releases.
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MVS also supports as a loopback address for compatibility with older releases.
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Use of the *ANY *ANY entry to route mail for unknown recipients via SMTP is not recommended because it may cause the mail to loop indefinitely.
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UUencode and UUdecode are a pair of UNIX utilities for encoding 8-bit binary data in a form that is safe for use with the UUCP program. This approach is in common use, but is not an Internet standard. It is inferior to MIME in most respects, but will safely transmit encoded 8-bit binary data through 7-bit ASCII gateways. It is not reliable through all gateways that perform ASCII-EBCDIC translation.
**** Footnote: 16***
RFC 822 format messages are not restricted to SMTP (RFC 821) networks but may be transmitted over any network supporting 7-bit ASCII (for example, UUCP networks). STD 11/RFC 822 format messages can also be encoded in EBCDIC and transmitted over RSCS/NJE networks, although problems arise with the mapping of certain characters such as ``['' and ``]'' which are syntactically important in RFC 822 header fields.
**** Footnote: 17***
The reason for this departure is that MIME allows for deeply nested encapsulation, but encodes text in such a way as to reversibly spill text lines at or before column 76 to avoid the lines being spilled irreversibly by non-conforming SMTP agents. The RFC 934 quoting mechanism can result in lines being lengthened with each level of encapsulation, possibly past column 76.
**** Footnote: 18***
The underscore character is not strictly mail-safe, but it is used because the use of any other character to indicate a SPACE would seriously hamper readability.
**** Footnote: 19***
System Object Model is the technology used to implement the object-oriented Workplace Shell Environment in OS/2 Version 2 and OS/2 Warp Version 3.
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A MIB view is a subset of the set of all instances of all object types defined according to SMI.
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snmpEventID.i is an SNMPv2 manager-to-manager MIB object which shows the authoritative identification of an event.
**** Footnote: 22***
ASN.1 BER specifies the Basic Encoding Rules according to ISO 8825 which are used in OSI Abstract Syntax Notation one.
**** Footnote: 23***
ILMI (Interim Local Management Interface) defined by ATM Forum to provide standardized management information and formats until the official ITU-T (former CCITT) standard is produced.
**** Footnote: 24***
UNI(User Network Interface)