18.4 Commands at a glance

Following is a list of commands related to satellite networking:

$ns_ node-config -satNodeType type
This node configuration declares that the subsequent new nodes created will be of type <type>, where <type> can be one of the following: geo, geo-repeater, polar, terminal. Other required fields for satellite nodes (for setting up initial links and channels) are as follows (see Section 5.3): $ns_ node-config -llType type
$ns_ node-config -ifqType type
$ns_ node-config -ifqLen length
$ns_ node-config -macType type
$ns_ node-config -channelType type
$ns_ node-config -downlinkBW value

(note- satNodeType geo-repeater only requires specifying the channelType- all other options are disregarded. See tcl/ex/sat-repeater.tcl for an example.)

$ns_ satnode-polar alt inc lon alpha plane linkargs chan
This a simulator wrapper method for creating a polar satellite node. Two links, uplink and downlink, are created along with two channels, uplink channel and downlink channel. <alt> is the polar satellite altitude, <inc> is orbit inclination w.r.t equator, <lon> is the longitude of ascending node, <alpha> gives the initial position of the satellite along this orbit, <plane> defines the plane of the polar satellite. <linkargs> is a list of link argument options that defines the network interface (like LL, Qtype, Qlim, PHY, MAC etc).

$ns_ satnode-geo lon linkargs chan
This is a wrapper method for creating a geo satellite node that first creates a satnode plus two link interfaces (uplink and downlink) plus two satellite channels (uplink and downlink). <chan> defines the type of channel.

$ns_ satnode-geo-repeater lon chan
This is a wrapper method for making a geo satellite repeater node that first creates a satnode plus two link interfaces (uplink and downlink) plus two satellite channels (uplink and downlink).

$ns_ satnode-terminal lat lon
This is a wrapper method that simply creates a terminal node. The <lat> and <lon> defines the latitude and longitude respectively of the terminal.

$ns_ satnode type args
This is a more primitive method for creating satnodes of type <type> which can be polar, geo or terminal.

$satnode add-interface type ll qtype qlim mac_bw phy
This is an internal method of Node/SatNode that sets up link layer, mac layer, interface queue and physical layer structures for the satellite nodes.

$satnode add-isl ltype node1 node2 bw qtype qlim
This method creates an ISL (inter-satellite link) between the two nodes. The link type (inter, intra or cross-seam), BW of the link, the queue-type and queue-limit are all specified.

$satnode add-gsl ltype opt_ll opt_ifq opt_qlim opt_mac opt_bw opt_phy opt_inlink opt_outlink
This method creates a GSL (ground to satellite link). First a network stack is created that is defined by LL, IfQ, Qlim, MAC, BW and PHY layers. Next the node is attached to the channel inlink and outlink.