netgear srx5308 internet speed slow

[Bridgford]

 My netgear srx 5308 only gives roughly 37mb internet speed even though there is a 200mb Virgin line.

Any ideas

[DaneA]

Hi @Bridgford,

Let us isolate the problem.  Kindly answer the questions below:

a. Are you connected via a wired connection directly to a LAN port of the SRX5308?  If not, kindly do the test again while your PC is directly connected to a LAN port of the SRX5308 and check the internet connection speed. 

b. Is the modem connected to the WAN port of the SRX5308 a modem-only device or a modem-router combination?

c. What is the current firmware version of the SRX5308?

Regards,

DaneA

NETGEAR Community Team

[Bridgford]

I am connected directly to a LAN port of the SRX5308 and i carried out a speed test.

This gave me 37mb down and 14 MB upload. This is from a Virgin 200MB line.

The Virgin modem is a modem router combination.

The latest firmware on the SRX5308 is 4.3.2-

[DaneA]

@Bridgford,

Thanks for the feedback.  Here are my suggestions:

1. Since the Virgin modem is a modem-router combination, I suggest you to configure it to full-bridge mode.  In this way, it will be set as a modem-only device and the Public WAN IP address will be registered to the WAN port of the SRX5308.

2. Upgrade the firmware of the SRX5308 to the latest version which is v4.3.5-3.  You can download it here.  Be sure to perform a factory reset after upgrading the firmware then reconfigure it from scratch in order to start clean using the latest firmware version.  

Let us know the results.

Regards,

DaneA

NETGEAR Community Team

[Bridgford]

Hi

Thank you for the information.

I have upgraded the Firmware to the latest and factory reset.

I could not make Hitron Virgin router a Modem only as i need the multiple ports on the back and if i make it a "modem" only, i would have lost them.

I connected a Draytek modem router and i had 130mb out of this router in normal mode.

Any other thoughts?

[DaneA]

@Bridgford,

Thanks for the feedback.  If you will not set the Hitron Virgin router to full bridge mode, you will have a Double NAT scenario in which this might be the reason why you are not able to get the internet speed you have subscribed through the SRX5308.  

For more information about Double NAT, kindly access the articles below:

What is Double NAT?

How to fix issues with Double NAT

Regards,

DaneA

NETGEAR Community Team

[fordem]

Whilst "doubleNAT" is not optimal, the fact that he can swap out the SRX5308 for a Draytek router and get an immediate and significant increase in throughput indicates that doubleNAT is NOT the cause of the slow down.

[Bridgford]

Thanks for information.

Any other ideas on how to improve speed through netgear srx5308.

[DaneA]

@Bridgford,

Kindly try this.  On the web-GUI of the SRX5308, go to Security > Firewall > Attack Checks then uncheck the boxes that says "Block TCP flood" and "Block UDP flood."  Then, observe if the same problem will occur.  Refer to the image below:

Regards,

DaneA

NETGEAR Community Team