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lltdscan - Scan for LLTD-enabled hosts on your network.
LLTD is a Link Layer Topology Discovery Protocol.
protocol specs are available from Microsoft at
Run "lltdscan -i em0" on your FreeBSD or Linux-based pc - and you'll
see all your neighbours that have the MS Windows installed and have
not unchecked the "Link-Layer Topology Discovery Responder" in their
Network Connection settings.
Works starting from XP(sp3 ?), works on Vista, needs testing on W2k7.
IMPORTANT: LLTD is a level 2 protocol - i.e. it not runs over ip or tcp or udp
or anything. So, you can get other PC's info even if they live in different IP
subnets, or even if they don't have any valid IP address but have 169.254.x.y
self-assigned IP.
FreeBSD: gmake && gmake install
Linux: make && cp lltdscan /usr/sbin/ && cp lltdscan.8 /usr/share/man/man8/
#sudo ./lltdscan -t1300
interface eth0
101 bytes from 00:01:33:ed:54:a1 ( ): time=929 ms name="XZ"
found 1 hosts in 1.303 seconds
#sudo ./lltdscan -t1300 -v
interface eth0
101 bytes from 00:01:33:ed:54:a1 ( ): time=929 ms name="XZ"
Host ID: 00 01 ee ff 22 a1
Charact.: 20 00 00 00 (full-duplex)
Media: 00 00 00 06 (Ethernet)
Perf.cntr: 00 00 00 00 00 36 9e 99
Link speed: 100 Mbit/s
Name: 31 00 43 00
QoS: 60 00 00 00 (802.1q-support, 802.1p-support)
found 1 hosts in 1.302 seconds
Public Domain.
zed [dot] 0xff [at]
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