DLSW protocol
U
SER
G
UIDE
303
DLSW
PROTOCOL
I
NTRODUCTION
Imola supports the Data Link Switching (DLSw) function, it is a forwarding mechanism for IBM SNA
networks based on Switch-to-Switch (SSP) protocol which encapsulates SNA frames in TCP/IP for
transport on Internet. The implementation complies with RFC 1795 specifications.
Before Data Link Switching begins, a TCP/IP connection must be established between two DLSw
extremes (peers); once this is established, the two peers exchange capabilities and, at this point,
they will use the SSP protocol in order to establish circuits on transport.
DLSW
CONFIGURATION
The local peer is defined by using its IP address, in the following way:
set dlsw local-peer ipaddr <ip address>
It is possible to define some additional proprieties for the local peer.
In order to configure a
keep-alive
between the local peer and its remote partner, the following
command is used:
set dlsw local-peer keepalive <seconds>
The value
0
means that no
keep-alive
will be activated (default setting). Valid values are between
0
and
1200
. In order to remove a keepalive setting and go back to the default value, the following
command is used:
set dlsw local-peer no-keepalive
In order to set a control window on the flow of packets exchanged between the two peers (pacing
window), as defined in RFC 1795, the following command is used:
set dlsw local-peer pacing-window <size>
The default value is
20
. Valid values are between
1
and
2000
.
The remote peer is defined by using its IP address as follows:
set dlsw remote-peer ipaddr <ip address>
During the configuration it is necessary to also set the MAC address of the SNA host which can be
reached through the remote peer:
set dlsw remote-peer target-mac <mac address>
The MAC address must be introduced as a sequence of 6 bytes separated by colons,
hh:kk:xx:yy:ww:zz
, by using hexadecimal notation.
It is possible to define a backup peer for the remote peer, with the command:
set dlsw remote-peer backup-peer <ip address>
In order to configure a resource which can be reached by a local peer, the following command is
used:
set dlsw icanreach mac-addr <mac address> [ mask <value> ]