Netgear DGND4000 Optimizer

Netgear DGND4000 (N750 WiFi DSL Modem Router - Premium Edition)

DGND4000 is an excellent router as such. Unfortunately it has a few issues that Netgear has no intention of fixing:

• It forces all DNS requests to go through the routers own forwarding service. Caching of requests is disabled ($$ business feature $$), so only effect is that every DNS request takes longer to complete.
• Number of concurrent connections (nf_conntrack_max) is set relatively low (compared to the routers hardware capacity)

Hardware specs:

• system type: 96362ADVN2xh
• cpu model: Broadcom4350 V7.0 (dual core)
• MemTotal: 124296 kB
• Kernel: Linux version 2.6.30 (root@BuildServer) (gcc version 4.4.2 (Buildroot 2010.02-git) ) #2 SMP PREEMPT Sat Feb 23 14:08:25 CST 2013

This little program will do the following:

• Enable telnet connections on 192.168.0.1
• Optimize kernel settings
• Set DNS to google's DNS service
• Disable unnecessary services to give more free memory and cpu cycles on router

Download

Date	Version	File	Description
26. Januar 2014	1.00	http://files.subsecret.dk/RouterSetup100.jar	Initial release (includes sourcecode)

Usage

java -jar RouterSetup100.jar ADMIN-PASSWORD

Newest official firmware

North America: http://www.downloads.netgear.com/files/GDC/DGND4000/DGND4000_V1.1.00.14_1.00.14NA.zip
Outside North America: http://www.downloads.netgear.com/files/GDC/DGND4000/DGND4000_V1.1.00.14_1.00.14.zip

Using telnet interface to change dsl settings

telnet 192.168.0.1

Enter admin password.
See current speed

# adslctl info --show
adslctl: ADSL driver and PHY status
Status: Showtime
Last Retrain Reason:    8000
Last initialization procedure status:   0
Max:    Upstream rate = 2158 Kbps, Downstream rate = 19232 Kbps
Bearer: 0, Upstream rate = 2044 Kbps, Downstream rate = 17915 Kbps   

Link Power State:       L0
Mode:                   ADSL2+ AnnexM EU-56
TPS-TC:                 ATM Mode
Trellis:                U:ON /D:ON
Line Status:            No Defect
Training Status:        Showtime
                Down            Up
SNR (dB):        6.1             7.5
Attn(dB):        22.0            15.9
Pwr(dBm):        18.6            12.9

Retrain connection with focus on maximum download speed (use --mod m for more upload speed)

# adslctl configure --mod a

Wait until connection is reestablished.
Check speed again

# adslctl info --show
adslctl: ADSL driver and PHY status
Status: Showtime
Last Retrain Reason:    8000
Last initialization procedure status:   0
Max:    Upstream rate = 1202 Kbps, Downstream rate = 20584 Kbps
Bearer: 0, Upstream rate = 1202 Kbps, Downstream rate = 19200 Kbps

Link Power State:       L0
Mode:                   ADSL2+ 
TPS-TC:                 ATM Mode
Trellis:                U:ON /D:ON
Line Status:            No Defect
Training Status:        Showtime
                Down            Up
SNR (dB):        6.1             7.7
Attn(dB):        21.0            13.2
Pwr(dBm):        18.5            12.1

So the speed was changed from 17915/2044 kbps to 19200/1202 kbps