Para termos uma idéia dos resultados obtidos, abaixo serão mostrados alguns testes que foram realizados e que provam a eficácia do modelo apresentado. Como já falado, o protocolo ICMP que fora alocado com prioridade máxima será o nosso mecanismo de teste.
Primeiramente, antes mesmo da execução do script de QoS, executando duas ações simultâneas, sendo estas um teste de ping e uma transferência de arquivo, podemos observar a latência dos pacotes ICMP.
a) PING para 64.233.179.104, sem quaisquer outras atividades de rede, sem QoS:
$ ping 64.233.179.104 -t
Pinging 64.233.179.104 with 32 bytes of data:
Reply from 64.233.179.104: bytes=32 time=190ms TTL=241
Reply from 64.233.179.104: bytes=32 time=192ms TTL=241
Reply from 64.233.179.104: bytes=32 time=192ms TTL=241
Reply from 64.233.179.104: bytes=32 time=190ms TTL=241
Reply from 64.233.179.104: bytes=32 time=196ms TTL=241
Reply from 64.233.179.104: bytes=32 time=192ms TTL=241
Reply from 64.233.179.104: bytes=32 time=197ms TTL=241
Reply from 64.233.179.104: bytes=32 time=196ms TTL=241
Reply from 64.233.179.104: bytes=32 time=193ms TTL=241
Reply from 64.233.179.104: bytes=32 time=197ms TTL=241
Reply from 64.233.179.104: bytes=32 time=192ms TTL=241
Reply from 64.233.179.104: bytes=32 time=192ms TTL=241
Reply from 64.233.179.104: bytes=32 time=196ms TTL=241
Reply from 64.233.179.104: bytes=32 time=193ms TTL=241
Reply from 64.233.179.104: bytes=32 time=197ms TTL=241
Reply from 64.233.179.104: bytes=32 time=197ms TTL=241
Reply from 64.233.179.104: bytes=32 time=196ms TTL=241
Reply from 64.233.179.104: bytes=32 time=192ms TTL=241
Reply from 64.233.179.104: bytes=32 time=193ms TTL=241
Reply from 64.233.179.104: bytes=32 time=188ms TTL=241
Reply from 64.233.179.104: bytes=32 time=192ms TTL=241
Reply from 64.233.179.104: bytes=32 time=187ms TTL=241
Reply from 64.233.179.104: bytes=32 time=197ms TTL=241
Reply from 64.233.179.104: bytes=32 time=200ms TTL=241
Reply from 64.233.179.104: bytes=32 time=193ms TTL=241
Reply from 64.233.179.104: bytes=32 time=193ms TTL=241
Reply from 64.233.179.104: bytes=32 time=192ms TTL=241
Reply from 64.233.179.104: bytes=32 time=189ms TTL=241
Reply from 64.233.179.104: bytes=32 time=192ms TTL=241
Reply from 64.233.179.104: bytes=32 time=188ms TTL=241
Reply from 64.233.179.104: bytes=32 time=192ms TTL=241
Reply from 64.233.179.104: bytes=32 time=197ms TTL=241
Reply from 64.233.179.104: bytes=32 time=196ms TTL=241
Reply from 64.233.179.104: bytes=32 time=193ms TTL=241
Ping statistics for 64.233.179.104:
Packets: Sent = 34, Received = 34, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 187ms, Maximum = 200ms, Average = 193ms
--- Latência não passa de 200ms.
b) PING para 64.233.179.104, no momento da transferência de um arquivo, com Qos habilitado.
Buscando imagem iso:
$ wget -c ftp://ftp.planetmirror.com/pub/Mandrake/devel/iso/10.1/i586/\
Mandrakelinux-10.1-Community-Download-CD1.i586.iso
...
0% [ ] 1,896,316 23.4K/s ETA 7:43:12
-- Taxa de transferência de 23Kbytes/s
Latência do PING:
$ ping 64.233.179.104 -t
Pinging 64.233.179.104 with 32 bytes of data:
Reply from 64.233.179.104: bytes=32 time=253ms TTL=241
Reply from 64.233.179.104: bytes=32 time=225ms TTL=241
Reply from 64.233.179.104: bytes=32 time=237ms TTL=241
Reply from 64.233.179.104: bytes=32 time=290ms TTL=241
Reply from 64.233.179.104: bytes=32 time=226ms TTL=241
Reply from 64.233.179.104: bytes=32 time=224ms TTL=241
Reply from 64.233.179.104: bytes=32 time=491ms TTL=241
Reply from 64.233.179.104: bytes=32 time=450ms TTL=241
Reply from 64.233.179.104: bytes=32 time=199ms TTL=241
Reply from 64.233.179.104: bytes=32 time=216ms TTL=241
Reply from 64.233.179.104: bytes=32 time=191ms TTL=241
Reply from 64.233.179.104: bytes=32 time=296ms TTL=241
Reply from 64.233.179.104: bytes=32 time=456ms TTL=241
Reply from 64.233.179.104: bytes=32 time=512ms TTL=241
Reply from 64.233.179.104: bytes=32 time=418ms TTL=241
Reply from 64.233.179.104: bytes=32 time=376ms TTL=241
Reply from 64.233.179.104: bytes=32 time=389ms TTL=241
Reply from 64.233.179.104: bytes=32 time=229ms TTL=241
Reply from 64.233.179.104: bytes=32 time=261ms TTL=241
Reply from 64.233.179.104: bytes=32 time=193ms TTL=241
Reply from 64.233.179.104: bytes=32 time=243ms TTL=241
Reply from 64.233.179.104: bytes=32 time=295ms TTL=241
Reply from 64.233.179.104: bytes=32 time=239ms TTL=241
Reply from 64.233.179.104: bytes=32 time=238ms TTL=241
Reply from 64.233.179.104: bytes=32 time=197ms TTL=241
Reply from 64.233.179.104: bytes=32 time=230ms TTL=241
Reply from 64.233.179.104: bytes=32 time=489ms TTL=241
Reply from 64.233.179.104: bytes=32 time=448ms TTL=241
Reply from 64.233.179.104: bytes=32 time=205ms TTL=241
Reply from 64.233.179.104: bytes=32 time=213ms TTL=241
Reply from 64.233.179.104: bytes=32 time=192ms TTL=241
Reply from 64.233.179.104: bytes=32 time=195ms TTL=241
Reply from 64.233.179.104: bytes=32 time=472ms TTL=241
Reply from 64.233.179.104: bytes=32 time=538ms TTL=241
Reply from 64.233.179.104: bytes=32 time=496ms TTL=241
Reply from 64.233.179.104: bytes=32 time=403ms TTL=241
Reply from 64.233.179.104: bytes=32 time=362ms TTL=241
Reply from 64.233.179.104: bytes=32 time=270ms TTL=241
Reply from 64.233.179.104: bytes=32 time=301ms TTL=241
Reply from 64.233.179.104: bytes=32 time=194ms TTL=241
Reply from 64.233.179.104: bytes=32 time=303ms TTL=241
Reply from 64.233.179.104: bytes=32 time=194ms TTL=241
Reply from 64.233.179.104: bytes=32 time=266ms TTL=241
Reply from 64.233.179.104: bytes=32 time=302ms TTL=241
Ping statistics for 64.233.179.104:
Packets: Sent = 44, Received = 44, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 191ms, Maximum = 538ms, Average = 304ms
--- Média de 300ms
c) Mantendo a transferência de arquivo, e removendo o QoS:
$ ping 64.233.179.104 -t
Pinging 64.233.179.104 with 32 bytes of data:
Reply from 64.233.179.104: bytes=32 time=1279ms TTL=241
Reply from 64.233.179.104: bytes=32 time=1316ms TTL=241
Reply from 64.233.179.104: bytes=32 time=1381ms TTL=241
Reply from 64.233.179.104: bytes=32 time=1435ms TTL=241
Reply from 64.233.179.104: bytes=32 time=1488ms TTL=241
Reply from 64.233.179.104: bytes=32 time=1541ms TTL=241
Reply from 64.233.179.104: bytes=32 time=1597ms TTL=241
Reply from 64.233.179.104: bytes=32 time=1647ms TTL=241
Reply from 64.233.179.104: bytes=32 time=1700ms TTL=241
Reply from 64.233.179.104: bytes=32 time=1753ms TTL=241
Reply from 64.233.179.104: bytes=32 time=1819ms TTL=241
Reply from 64.233.179.104: bytes=32 time=1868ms TTL=241
Reply from 64.233.179.104: bytes=32 time=1859ms TTL=241
Request timed out.
Reply from 64.233.179.104: bytes=32 time=2069ms TTL=241
Reply from 64.233.179.104: bytes=32 time=2124ms TTL=241
Reply from 64.233.179.104: bytes=32 time=2180ms TTL=241
Ping statistics for 64.233.179.104:
Packets: Sent = 17, Received = 16, Lost = 1 (5% loss),
Approximate round trip times in milli-seconds:
Minimum = 1279ms, Maximum = 2180ms, Average = 1691ms
---- Máximo de 2 segundos!!!!!! E ainda observamos perda de pacote!!!
Com isto, pudemos comprovar o funcionamento do script apresentado.
Quaisquer dúvidas, esclarecimentos ou mesmo críticas (construtivas :) ), pode entrar em contato.
Abs a todos!
Gustavo Carvalho