==                                                  NOSview [301]
ip
==

The 'ip' commands are used for configuring and monitoring the
Internet Protocol (IP).

You need to have a unique IP address before you can link in with
the rest of the networked world.  The best way to get one is to
ask around the local packet community and find out who your local
address coordinator is.  Your local coordinator will then assign
you an address from the block for your area.

IP addresses are 32-bit numbers that uniquely identify a given
machine (or "host") running the TCP/IP protocol suite.  These
numbers are usually broken down into four dot-separated fields of
eight bits, each field being expressed as a decimal number in the
range 0-255.

Thus, for example, the 32-bit binary IP address

          00101100 00000001 10000000 00001001

would be expressed as 44.1.128.9 decimal.

In some older versions of NOS, square brackets were used to
indicate IP addresses; e.g. [44.1.128.9].

The worldwide allocation of IP addresses is coordinated by the
Network Information Center (NIC) in the United States.  Amateur
radio operators have been allocated a so-called "Class A"
network, with addresses in the 44.x.x.x series.

If you have not yet obtained your IP address and want to get on
the air immediately, you may temporarily use 44.128.0.x, where
'x' is a decimal number between 1 and 254.  Try to be sure that
no one else in your area is using the same number.

_________________________________________________________________
ip access  permit|deny|delete  <dest_ip_addr>|all[/<bits>]
                      <interface> [ <lowport>|none [ <higport> ]]
_________________________________________________________________
Set or display access control for IP routing functions.  This
command implements router access functions to NosFp.

'permit' enables dest_ip_address packets to be routed via
<interface>.

'deny' disables those.

If <lowport> is not given, all ports are assumed.

If only <lowport> is given, that port is only checked for
permission.

If <lowport> and <highport> are given, that is the range of ports
permitted/denied.

<dest_ip_address> can be the word 'all' for all addresses
possible.

<lowport> can be the word 'none' for all ports.

The 'ip access delete' must match a previously defined 'permit'
or 'deny' to be able to delete that definition.

If no access list is created, all interfaces might carry all
types.  If an access control is defined for an interface there
must be a 'permit' defined for that interface to allow traffic.
Thus a partial denial without a 'permit' is an complete denial.

>> Examples:  ip access permit 44/8 tnc0
              ip access deny all tnc0 1 1023
              ip access permit all tnc0


_________________________________________________________________
ip address [<ip_address> | <hostname>]
_________________________________________________________________
Display or set the default local IP address.  This command must
be given before an 'attach' command if it is to be used as the
default IP address for the interface.

The <ip_address> is in the usual dotted decimal format.

If you use the hostname to set the IP address, <hostname> must
exist in the hosts file /domain.txt.

>> Examples:  ip address 44.199.41.1
              ip address ns9bob


_________________________________________________________________
ip rtimer [<seconds>]                                 Default: 30
_________________________________________________________________
Display or set the IP reassembly timeout.  The timer is re-
initialised whenever progress is made in reassembling a datagram
(i.e. a new fragment is received).

It is not necessary that all of the fragments belong to a
datagram arrive within a single timeout interval, only that the
interval between fragments be less than the timeout.

>> Example:  ip rtimer 60


_________________________________________________________________
ip status
_________________________________________________________________
Display Internet Protocol (IP) statistics, such as total packet
counts and error counters of various types.


_________________________________________________________________
ip ttl [<hops>]                                      Default: 255
_________________________________________________________________
Display or set the time-to-live value placed in each outgoing IP
datagram.  This limits the number of hops the datagram will be
allowed to take.  The idea is to bound the lifetime of the packet
should it become caught in a routing loop, so make the value
slightly larger than the number of hops across the network you
expect the packets to make.

>> Example:  ip ttl 10
