4.3. Microsoft Windows

Most of the tools we have been discussing are available in one form or another for Windows platforms. Microsoft's implementation of traceroute, known as tracert, has both superficial and fundamental differences from the original implementation. Like ping, tracert requires a DOS window to run. We have already seen an example of its output. tracert has fewer options, and there are some superficial differences in their flags. But most of traceroute's options are rarely used anyway, so this isn't much of a problem.

A more fundamental difference between Microsoft's tracert and its Unix relative is that tracert uses ICMP packets rather than UDP packets. This isn't necessarily bad, just different. In fact, if you have access to both traceroute and tracert, you may be able to use this to your advantage in some unusual circumstances. Its behavior may be surprising in some cases. One obvious implication is that routers that block ICMP messages will block tracert, while traceroute's UDP packets will be passed.

As noted earlier in this chapter, Mentor's Java implementation of ttcp runs under Windows if you can find it. Both netperf and iperf have also been ported to Windows. Another freely available program worth considering is Qcheck from Ganymede Software, Inc. This program requires that Ganymede's Performance Endpoints software be installed on systems at each end of the link. This software is also provided at no cost and is available for a wide variety of systems ranging from Windows to MVS. In addition to supporting IP, the software supports SPX and IPX protocols. The software provides ping-like connectivity checks, as well as response time and throughput measurements.

As noted in Chapter 2, "Host Configurations", Microsoft also provides its own version of netstat. The options of interest here are -e and -s. The -e option gives a brief summary of activity on any Ethernet interface:

C:\>netstat -e
Interface Statistics

                           Received            Sent

Bytes                       9840233         2475741
Unicast packets               15327           16414
Non-unicast packets            9268             174
Discards                          0               0
Errors                            0               0
Unknown protocols               969

The -s option gives the per-protocol statistics:

C:\>netstat -s

IP Statistics

  Packets Received                   = 22070
  Received Header Errors             = 0
  Received Address Errors            = 6
  Datagrams Forwarded                = 0
  Unknown Protocols Received         = 0
  Received Packets Discarded         = 0
  Received Packets Delivered         = 22064
  Output Requests                    = 16473
  Routing Discards                   = 0
  Discarded Output Packets           = 0
  Output Packet No Route             = 0
  Reassembly Required                = 0
  Reassembly Successful              = 0
  Reassembly Failures                = 0
  Datagrams Successfully Fragmented  = 0
  Datagrams Failing Fragmentation    = 0
  Fragments Created                  = 0

ICMP Statistics

                            Received    Sent
  Messages                  20          8
  Errors                    0           0
  Destination Unreachable   18          8
  Time Exceeded             0           0
  Parameter Problems        0           0
  Source Quenchs            0           0
  Redirects                 0           0
  Echos                     0           0
  Echo Replies              0           0
  Timestamps                0           0
  Timestamp Replies         0           0
  Address Masks             0           0
  Address Mask Replies      0           0

TCP Statistics

  Active Opens                        = 489
  Passive Opens                       = 2
  Failed Connection Attempts          = 69
  Reset Connections                   = 66
  Current Connections                 = 4
  Segments Received                   = 12548
  Segments Sent                       = 13614
  Segments Retransmitted              = 134

UDP Statistics

  Datagrams Received    = 8654
  No Ports              = 860
  Receive Errors        = 0
  Datagrams Sent        = 2717

Interpretation is basically the same as with the Unix version.

---