DSL modem must be NAT .. do I need a router?

[Breezy]

I've tried to find an answer to this but cannot so maybe it's so elemental as to be obvious but I ask ..

I have a home network consisting of an unmanaged giga switch, a 10/100 wireless router, a NAS, two Directv connections, two Windows boxes, a printer, and an internet connection via a Westell DSL modem.

My ISP has informed me that the modem must be the NAT so now the router is bridged. It all works but it seems like there is some latency in the system and I would like to simplify the layout and maybe reduce the devices involved.

This got me to thinking .. since the NAT is in the modem can I just run it to a switch, preferably a managed switch so that low speed connections, don't effect throughput, and then just use the existing router as a wireless access point?

Right now I'm noticing that seemingly any network traffic slows down my NAS to pc bandwidth and I would like to isolate that so that I get full bandwidth for this pc to NAS connection.

 

[thiggins]

Please provide exact model # of the router and Westell modem.

 

[Breezy]

Westell 6100 modem.
The router is a DLink WBR 2310 in bridged config.

I'm now running the modem into my giga switch Dlink DGS 2208, along with my other gigabit capable devices .. the two pcs and the NAS .. and then a connection to the router. The router is connecting to my slower devices (printer, Directv connections)

The biggest issue in all this is just how much slower a network is at accessing files on the NAS. Typically it takes more than twice as long to open a file that sits on the NAS than a local drive or even an external USB drive. Right now that keeps me from using the NAS as a central depository for files, which was the whole point of this setup. Maybe I have the wrong NAS but it specs out pretty decent and I'm getting 38 mb sec writes and 48 mb sec reads from it. When I open a file though the transfer rate is very slow, at about 5 mb sec.

 

[thiggins]

A network diagram would help.

The Westell 6100 is, in fact a router. So connecting its LAN port to your Gigabit switch is fine.

I don't think the WBR2310 has a "bridged" mode. So it would help to understand exactly how you have it configured and connected.

The biggest issue in all this is just how much slower a network is at accessing files on the NAS.

It would help if you define "a network". Wired or wireless access.

 

[Breezy]

Sorry for the delay. Here's a link to crude sketch.
Across the top from left to right is the router being used only as an access point, the switch, and the Westell router. All cabling is Cat5E or 6.

http://imm.io/3Ywv

I'm considering that many of my issues are coming from a NAS itself, a QNAP 119P+

Read/write speeds to the NAS vary tremendously from the same machines, only a minute or two apart. I'm trying to make sure I can have maximum small file opening performance and it bothers me that when you tested this NAS it would not pass the office productivity tests.

Do you think I have much latency in this layout for the wired portion of the network since the NAT is stored in the Westell modem/router? I'm trying to get office app files to open faster.

 

[thiggins]

LAN transfers do not touch the routing portion of the router. They just flow through the switch. To make sure that the router isn't affecting anything, assign static IP addresses to the NAS and the computers you are testing and run your tests after disconnecting the AP and WBR2310 and Westell modem.