|-u bufsize||Sets the send/receive buffer size in bytes. Default value will be automatically calculated based on transfer speed, packet size and host timer accuracy.|
|-r reporting_period||Sets the interval time in seconds between periodic bandwidth, RTT, and loss reports. If zero, there will be no periodic reports (default).|
|-T tos (bwping only)||Sets the TOS value of outgoing ip packets. Default value is zero.|
|-T tclass (bwping6 only)||Sets the IPv6 Traffic Class value of outgoing ip packets. Default value is zero.|
|-B bind_addr||Sets the source address of outgoing ip packets. By default the address of the outgoing interface will be used.|
|-b kbps||Sets the transfer speed in kilobits per second.|
|-s pktsize||Sets the packet size in bytes.|
|-v volume||Sets the volume to transfer in bytes.|
Oleg Derevenetz <email@example.com>
This utility uses raw sockets to deal with ICMP messages, so root privileges are required to run it.
Although bwping and bwping6 does not require any special software on the remote host (only the ability to respond on ICMP echo request messages), there are some special requirements to network infrastructure, local and remote host performance:
1. There should be no ICMP echo request/reply filtering on the network. This includes QoS mechanisms (which often affects ICMP) at any point in the testing path;
2. Local host should have enough CPU resources to send ICMP echo request messages with given rate, and remote host should quickly respond on these messages and should have no ICMP bandwidth limiting turned on.
If some of these requirements are not satisfied, then measurement results will be inadequate or fail completely. In general, for testing bandwidth where QoS is implemented, always test with traffic that matches the QoS class to be tested.