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Ethernet Driver ( ethd)

 

The ethd protocol is the ``device driver'' that a host uses to connect to either an Ethernet or a point-to-point link. The following arguments for ethd may be specified on an args or

pargs line.

-ethdDelay=<integer>

Used to simulate the time it takes, in microseconds, for a host to process a packet. During the time period specified, the host cannot accept or process any other packets. If this option is not specified, hosts are assumed to be infinitely fast.

-ethdDelayRange=<integer>

A random number of microseconds is added to each delay period specified by -ethdDelay. If the argument given is x, then the interval of the modification is between -x and x. Note that the range specified should be less than or equal to the delay specified using -ethdDelay.

-ethdQueue=<integer>

Specifies the maximum number of messages that can be queued for transmission by ETHD. This is useful when using hosts running IP as routers; it is the only way to specify the maximum queue size for the router outports.

-ethdTrace=<integer>[:<integer>]

Indicates that the Ethernet driver protocol should save trace information (e.g., opens, sends, drops) and specifies the amounts of memory and disk space that may be used for this purpose. The first integer argument specifies the size, in trace entries (about 8 bytes each), of the circular buffer used to hold trace information in memory. If no colon and second argument is specified, this number also represents the maximum size of the trace file. The second argument specifies the maximum number of memory buffers that the disk file may contain. See the explanation of shorttrace in Section 3.4.1 for an example.

-ethdTraceIn

In conjunction with -ethdTrace, traces the average number of bytes/second arriving on the interface associated with the ethd driver.

-ethdTraceOut

In conjunction with -ethdTrace, traces the average number of bytes/second sent on the interface associated with ethd



next up previous contents
Next: Big Window TCP Up: The host Entry Previous: Simulator Interface (



Larry Peterson
Mon Jun 24 16:40:03 MST 1996