On testing the NETBLT Protocol over divers networks (RFC1030)
Original Publication Date: 1987-Nov-01
Included in the Prior Art Database: 2019-Feb-15
Internet Society Requests For Comment (RFCs)
This memo describes the results gathered from testing NETBLT over three networks of different bandwidths and round-trip delays. The results are not complete, but the information gathered so far has not been promising. The NETBLT protocol is specified in RFC-998; this document assumes an understanding of the specification as described in RFC-998.
Network Working Group M. Lambert Request for Comments: 1030 M.I.T. Laboratory for Computer Science November 1987
On Testing the NETBLT Protocol over Divers Networks
STATUS OF THIS MEMO
This RFC describes the results gathered from testing NETBLT over three networks of differing bandwidths and round-trip delays. While the results are not complete, the information gathered so far has been very promising and supports RFC-998’s assertion that that NETBLT can provide very high throughput over networks with very different characteristics. Distribution of this memo is unlimited.
NETBLT (NETwork BLock Transfer) is a transport level protocol intended for the rapid transfer of a large quantity of data between computers. It provides a transfer that is reliable and flow controlled, and is designed to provide maximum throughput over a wide variety of networks. The NETBLT protocol is specified in RFC-998; this document assumes an understanding of the specification as described in RFC-998.
Tests over three different networks are described in this document. The first network, a 10 megabit-per-second Proteon Token Ring, served as a "reference environment" to determine NETBLT’s best possible performance. The second network, a 10 megabit-per-second Ethernet, served as an access path to the third network, the 3 megabit-per- second Wideband satellite network. Determining NETBLT’s performance over the Ethernet allowed us to account for Ethernet-caused behaviour in NETBLT transfers that used the Wideband network. Test results for each network are described in separate sections. The final section presents some conclusions and further directions of research. The document’s appendices list test results in detail.
Many thanks are due Bob Braden, Stephen Casner, and Annette DeSchon of ISI for the time they spent analyzing and commenting on test results gathered at the ISI end of the NETBLT Wideband network tests. Bob Braden was also responsible for porting the IBM PC/AT NETBLT implementation to a SUN-3 workstation running UNIX. Thanks are also due Mike Brescia, Steven Storch, Claudio Topolcic and others at BBN who provided much useful information about the Wideband network, and
M. Lambert [Page 1]
RFC 1030 Testing the NETBLT Protocol November 1987
helped monitor it during testing.
3. Implementations and Test Programs
This section briefly describes the NETBLT implementations and test programs used in the testing. Currently, NETBLT runs on three machine types: Symbolics LISP machines, IBM PC/ATs, and SUN-3s. The test results described in this paper were gathered using the IBM PC/AT and SUN-3 NETBLT implementations. The IBM and SUN implementations are very similar; most differences lie in timer and multi-tasking library implementations. The SUN NETBLT implementation uses UNIX’s user-accessible raw IP socket; it is not implemented in the UNIX kernel.
The test application performs a simple memory-to-memory transfer of an arbitrary amount of...