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No rights are granted, in any manner or form, to use Whistle .\" Communications, Inc. trademarks, including the mark "WHISTLE .\" COMMUNICATIONS" on advertising, endorsements, or otherwise except as .\" such appears in the above copyright notice or in the software. .\" .\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND .\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO .\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, .\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF .\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. .\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY .\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS .\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. .\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES .\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING .\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, .\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR .\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY .\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF .\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY .\" OF SUCH DAMAGE. .\" .\" Author: Archie Cobbs .\" .\" $FreeBSD$ .\" $Whistle: ng_cisco.8,v 1.5 1999/01/25 23:46:26 archie Exp $ .\" .Dd January 19, 1999 .Dt NG_CISCO 8 .Os FreeBSD 3 .Sh NAME .Nm ng_cisco .Nd Cisco HDLC protocol netgraph node type .Sh SYNOPSIS .Fd #include .Sh DESCRIPTION The .Nm cisco node type performs encapsulation and de-encapsulation of packets using the Cisco HDLC protocol. This is a fairly simple protocol for the transmission of packets across high speed synchronous lines. Each packet is prepended with an Ethertype, indicating the protocol. There is also a ``keep alive'' and an ``inquire'' capability. .Pp The .Dv downstream hook should connect to the synchronous line. On the other side of the node are the .Dv inet , .Dv atalk , and .Dv ipx hooks, which transmit and receive raw IP, AppleTalk, and IPX packets, respectively. Typically these hooks would connect to the corresponding hooks on an .Xr ng_iface 8 type node. .Sh IP Configuration In order to function properly for IP traffic, the node must be informed of the local IP address and netmask setting. This is because the protocol includes an ``inquire'' packet which we must be prepared to answer. There are two ways to acomplish this, manually and automatically. .Pp Whenever such an inquire packet is received, the node sends a .Dv NGM_CISCO_GET_IPADDR control message to the peer node connected to the .Dv inet hook (if any). If the peer responds, then that response is used. This is the automatic method. .Pp If the peer does not respond, the node falls back on its cached value for the IP address and netmask. This cached value can be set at any time with a .Dv NGM_CISCO_SET_IPADDR message, and this is the manual method. .Pp If the .Dv inet hook is connected to the .Dv inet hook of an .Xr ng_iface 8 node, as is usually the case, then configuration is automatic as the .Xr ng_iface 8 understands the .Dv NGM_CISCO_GET_IPADDR message. .Sh HOOKS This node type supports the following hooks: .Pp .Bl -tag -width foobarbazio .It Dv downstream The connection to the synchronous line. .It Dv inet IP hook. .It Dv atalk AppleTalk hook. .It Dv ipx IPX hook .El .Sh CONTROL MESSAGES This node type supports the generic control messages, plus the following: .Bl -tag -width foo .It Dv NGM_CISCO_SET_IPADDR This command takes an array of two .Dv "struct in_addr" arguments. The first is the IP address of the corresponding interface and the second is the netmask. .It Dv NGM_CISCO_GET_IPADDR This command returns the IP configuration in the same format used by .Dv NGM_CISCO_SET_IPADDR . This command is also .Em sent by this node type to the .Dv inet peer whenever an IP address inquiry packet is received. .It Dv NGM_CISCO_GET_STATUS Returns a .Dv "struct ngciscostat" : .Bd -literal -offset 4n struct ngciscostat { u_int32_t seq_retries; /* # unack'd retries */ u_int32_t keepalive_period; /* in seconds */ }; .Ed .El .Sh SHUTDOWN This node shuts down upon receipt of a .Dv NGM_SHUTDOWN control message, or when all hooks have been disconnected. .Sh BUGS Not all of the functionality has been implemented. For example, the node does not support querying the remote end for its IP address and netmask. .Sh SEE ALSO .Xr netgraph 4 , .Xr ng_iface 8 , .Xr ngctl 8 . .Rs .%A D. Perkins .%T "Requirements for an Internet Standard Point-to-Point Protocol" .%O RFC 1547 .Re .Sh LEGAL Cisco is a trademark of Cisco Systems, Inc. .Sh AUTHORS Julian Elisher , Archie Cobbs