Comcast 105, Linksys E3000, Linksys AE1000, and 24mbps.

[netmon11]

Hello all!

Here is my question... I have Comcast 105 (yes, 105.) I recently ran a speed test to my local server, and returned with the following speed test results:



I am pretty dissatisfied with the state of my speeds, wireless or not, since I am using 802.11n products, in close proximity to the AP. If I go wired, it shoots right up to 100-112mbps no problem, so I am looking for advice on my wireless situation. BTW - since those of you will ask, no, I cannot go wired. The AP is in my living room, and not in my office. I have no coax drops in my office, nor do I have rj-45 strewn about my house or punched down. Running cable along the floor boards is not an option due to little ones, and I refuse to run it along the ceiling... it looks like crap.

I recently did TCP optimizer... here is the output from that:

##############################
TCP Window Auto-Tuning=normal
Congestion Control Provider=ctcp
TCP Chimney Offload=enabled
Receive-Side Scaling State=enabled
EnableDCA=enabled
EnableTCPA=enabled
DefaultTTL=64
ECN Capability=disabled
Windows Scaling heuristics=disabled
Tcp1323Opts=1
DisableTaskOffload=0
MaxConnectionsPer1_0Server=8
MaxConnectionsPerServer=8
LocalPriority=4
HostsPriority=5
DnsPriority=6
NetbtPriority=7
SynAttackProtect=1
TCPMaxDataRetransmissions=7
LargeSystemCache=1
Size=2
NonBestEffortLimit=0
NegativeCacheTime=0
NetFailureCacheTime=0
NegativeSOACacheTime=0
TCPNoDelay=-1
MaxUserPort=65534
NetworkThrottlingIndex=-1
TcpTimedWaitDelay=30
[Wireless Network Connection]
MTU=1500
TcpAckFrequency=-1
TcpDelAckTicks=-1
[Wireless Network Connection 3]
MTU=1500
TcpAckFrequency=-1
TcpDelAckTicks=-1
[Local Area Connection]
MTU=1500
TcpAckFrequency=-1
TcpDelAckTicks=-1
[Wireless Network Connection 2]
MTU=1500
TcpAckFrequency=-1
TcpDelAckTicks=-1
##############################

Here is the output from TCP Analyzer:

##############################
TCP options string = 020405b40103030801010402
MTU = 1500
MTU is fully optimized for broadband.
MSS = 1460
Maximum useful data in each packet = 1460, which equals MSS.
Default TCP Receive Window (RWIN) = 65536
RWIN Scaling (RFC1323) = 8 bits (scale factor: 2^8=256)
Unscaled TCP Receive Window = 256

In Windows 7, unless "TCP/IP Auto-Tuning" is disabled, only the Current TCP Window is displayed. Use the latest TCP Optimizer for tweaking.
You seem to be using Google Chrome. Note that Chrome can modify the TCP Window for sockets it creates under some OSes, and therefore servers may not get your corret RWIN value. You may want to test with a different browser. FAQ
RWIN is not fully optimized. The unscaled RWIN value is lower than it should be. Also, RWIN being close to and above 65535 does not justify the header overhead of enabling TCP 1323 Options. You might want to use one of the recommended RWIN values below.

For optimum performance, consider changing RWIN to a multiple of MSS.
Other RWIN values that might work well with your current MTU/MSS:
64240 (up to 2 Mbit lines, depending on latency. MSS * 44)
128480 (1-5 Mbit lines, depending on latency. MSS * 44 * 2)
256960 (2-14 Mbit lines, depending on latency. MSS * 44 * 2^2)
513920 (8-30 Mbit lines, depending on latency. MSS * 44 * 2^3)
1027840 (25-60 Mbit lines depending on latency. MSS * 44 * 2^4)
bandwidth * delay product (Note this is not a speed test):

Your TCP Window limits you to: 2621 kbps (328 KBytes/s) @ 200ms
Your TCP Window limits you to: 1049 kbps (131 KBytes/s) @ 500ms
MTU Discovery (RFC1191) = ON
Time to live left = 117 hops
TTL value is ok.
Timestamps (RFC1323) = OFF
Selective Acknowledgements (RFC2018) = ON
IP type of service field (RFC1349) = 00000000 (0)
##############################

Here is a tracert from my spot to google.com (close IPs omitted for privacy)

##############################
Tracing route to google.com [74.125.115.99]
over a maximum of 30 hops:

1 <1 ms <1 ms <1 ms <This is Me>
2 35 ms 19 ms 20 ms hop
3 8 ms 11 ms 12 ms hop
4 13 ms 9 ms 9 ms hop
5 10 ms 11 ms 11 ms hop
6 12 ms 14 ms 14 ms hop
7 14 ms 13 ms 14 ms hop
8 19 ms 21 ms 19 ms hop
9 20 ms 21 ms 23 ms hop
10 32 ms 35 ms 32 ms hop
11 32 ms 30 ms 28 ms hop
12 * 33 ms 40 ms hop
13 30 ms 34 ms 30 ms google! [74.125.115.99]

Trace complete.
##############################

Thanks in advance for any insight and advice!

-nm11

[Philip]

There seems to be a bit too much latency to hop 2, is that local to you (cable modem) or not ?

Make sure that you keep the wireless router away from possible sources of EMI, i.e. at least 1 foot away from the cable modem, power supplies, fluorescent lights, etc.
Also, I'd disable "mixed" G and N mode in the wireless router and change it to "N"-only for best throughput. Is the client using a "N" NIC as well ?

Check the Bits/Bytes calculator here: http://www.speedguide.net/conversion.php and note that there are different classes of "N" wireless products. Some are 150Mbps, some are 300Mbps, and only a few work up to 450Mbps. Many wireless NICs only work at the lower "N" speeds. With that in mind, a 150Mbps NIC is capable of ~17 Megabytes/second in both directions, 300Mbps = ~35Mbytes/sec...



I hope this helps