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Analysis of the new modem-router with Wi-Fi N provided by Jazztel

External analysis

The router is presented in its box with all its accessories and documentation that we have to review well.

  • Router.
  • Current transformer.
  • Network cable (Yellow cable).
  • Telephone cable (Gray cable).
  • 2 Microfilters, to connect them to telephones.
  • TWIN line splitter (To connect the router and a telephone to the line).
  • CD with manuals (In English and Spanish) and utilities.
  • Additional stickers in case we want to change the SSID and the Wi-Fi key.

The equipment has a more compact size (small) than those that Jazztel distributed up to now, although we observe a casing with low-quality materials, we see current components and well-designed electronics inside, the dissipation of the components and the power supply switched in class D (PWM) are highly efficient and thermal dissipation has been reduced compared to the previous model (CT-536B) that became the object of modding with curious ventilation solutions …

Jazztel this time has opted for a white and austere design with its logo larger than usual, the case is made up of three pieces, which we will see later.

In the back we will see the connections, ethernet network, ADSL (RJ11 socket), power supply and USB socket. Jazztel has cataloged the color of the connectors with the color of the cables to help the user intuitively in the configuration and assembly of the equipment and avoid basic errors.

As a novelty among Jazztel modem routers, this model includes a USB port to connect USB disks or printers. If they are connected to these ports, the router is able to share its resources in all the PCs that we connect to the router. We will see a disk performance test later.

In this router model, all its LAN connectors with IEEE 802.3, IEEE 802.3u, 10/100 BaseT auto-sense standards and with automatic MDI / MDIX (normal / crossover cable) support are available to connect up to 4 PCs, as in other models x3 and x4 connectors were reserved for IP television and IP telephony. This router is not distributed for Jazztelia, so all ports are free.

Right next to it we have the ADSL (WAN) interface to connect it to the line, this interface supports the standards:

  • ADSL ITU-T G.992.5
  • ITU-T G.992.3
  • ITU-T G.992.1
  • ANSI T1.413 Issue 2
  • G.DMT (ADSL) Download: 8 Mb / s – Upload: 832 Kb / s
  • G.992.3 (ADSL2) Download: 12 Mb / s – Upload: 1.3 Mb / s
  • G.992.5 (ADSL2 +) Download: 24 Mb / s – Upload: 1.3 Mb / s
  • Annex M (ADSL2 +) Download 24Mb / s – Upload: 2,5 Mb / s
  • VPN pass-through for IPSec
  • L2TP
  • PPTP
  • With internal firewall and most common functions

Where is the reset button? Look no further, it’s at the front. In the Comtrend AR-5381u it is much more accessible in case we need it. If not for the name β€œRESET” that appears, the button is very disguised.

The function indicators (LEDs) in this case are much larger and always green, as is normal the only red is “ALARM”, but it is clear that we never want to see that LED lit up. As I mentioned earlier, it is a fairly simple and austere design but very practical.

Where are the antennas? Are you sure it’s a Wifi router?
Well, indeed, it is a Wifi router. The antennas have disappeared from the outside as is normal in the latest designs that we see in stores to give it a more elegant and simplistic touch (or to avoid breaking them ..). They are arranged internally, we see them in the following images.

Just below, we can see the sticker that Jazztel leaves us with the factory Wi-Fi connection values. With the SSID and the key so that we can connect from the first day. The detail of having a couple of replacement adhesive labels is appreciated in case we want to change the parameters and write them down.

Here we see how the router works at full performance, there is already P2P traffic.

Internal analisis

Well, here we have the guts of the Comtrend. As you will see, it is a much more compact design. Of course you will have noticed that the Wireless card is now integrated into the board. It no longer has the MiniPCI card that characterized the previous models (CT-536B). Its circuitry is made up of Broadcom’s BCM433225KMLG reference, complies with Wireless IEEE 802.11 b / g / n standards, and guarantees a speed of up to 300Mb / s. The two antennas allow 2T / 2R MIMO. Supports AP and WDS functions

The available ciphers are:
WEP 64 and 128 bits, WPA (TKIP) WPA-PSK (TKIP) WPA2 (AES) WPA2-PSK (AES) 802.1X (EAP-MD5 / TLS / TTLS / PEAP) WDS: WMM (QoS) WPS (Wi-Fi Protected Setup)

Very close to the Wireless is the CPU (it is a DSP that includes the analog part of the BRL splitter for the adsl), it is located under the heatsink. It is appreciated that you have this heatsink since Broadcom CPUs acquire quite high temperatures. This model equips the BCM963281KFBG CPU, an updated version of the same CPU that the CT-536B used with different packaging.

Right between the main chipset and the Wireless chipset is the router’s RAM (temporary) with a capacity of 64MB

We have turned the motherboard around and found Flash memory (where it stores program and configuration variables) with a capacity of 8MB.

Did you really think that the router had no antennas? yes it does, they are arranged inside the box and have a gain of 2.3dB. Its performance is correct and its greatest advantage will be found with the use of a Wi-Fi N adapter, with the current adapter we will obtain a lower link quality since the maximum power has been reduced from 19dB to 17dB to respect the specifications of the 802.11 N standard.

Test laboratory

Synchronism speed and line status. In this section we will be able to see in what state our ADSL line is, to carry out this analysis we have a connection of 6Mb / download for 1Mb / upload with Jazztel of the service provider. In the lower screenshot we can see the exact synchronism speed and the status of the line.

Unfortunately the state of the line is not ideal, but at least 99% of the contracted speed is obtained, so the timing is quite correct.

HTTP direct download testing. Well, we enter the matter that interests us. Here we can see how this router works.

Test Scenario # 1

Equipment used to perform the analysis: desktop PC with Windows XP SP3 and Mozilla Firefox 3.6.12 browser connected by network cable to the Comtrend AR-5381u. An ISO of Ubuntu 10.10 has been downloaded from its official website.

It took a total of 18 minutes to download the ISO at a constant speed of 595-610 KB / s. The download has been quite stable.

ADSLZONE speed test. It is obtained only with a PC connected by cable, without any active download, neither by P2P nor by HTTP.

Review Comtrend AR-5381u

The speed of the test is correct, the ping could be improved, but it is within normal values.

Test Scenario # 2

Equipment used: TOSHIBA Netbook NB-100 with Windows 7 Professional x86 system and a Wireless Ubiquiti SR71-E a / b / g / n MIMO card with Atheros AR9280 chipset. It is Wireless IEEE 802.11n type.

NOTE: For optimal performance, it is essential to have the WMM option activated in the advanced properties of the router.

Review Comtrend AR-5381uReview Comtrend AR-5381u

As an important fact, I tell you that between the PC and the router there is a distance of about 15 meters plus 3 walls in between.

Wifi performance test with InSSIDer:

Review Comtrend AR-5381u

It is clear, the stability in the Wireless, it is clear, this chipset has improved a lot. There is not a single ups and downs.

Try direct download. The same Ubuntu ISO has been downloaded as in the previous test.

Review Comtrend AR-5381u

Quite stable, from the first moment it has reached a speed of 640KB / s and it has been maintained for several minutes, the average speed has been about 612KB / s.

As you can see, even with a certain distance (15 meters) and several walls in between, it does not lose any performance at all, it is even higher than through network cable, since its speed is 270Mbps while that of Ethernet 100Mbps.

ADSLZONE speed test

Review Comtrend AR-5381u

Here too it is obvious that performance is not lost. All this thanks to its Broadcom chipset with IEEE 802.11n technology.

It’s not bad at all. Think of it as a Wireless-N MIMO adapter so even though it is far from the router, the differences with Ethernet should be minimal. As I said, you must have WMM activated in the advanced options of the Wireless menu.

Test Scenario # 3

Test file transfer from PC to PC. The TOSHIBA connected by Wi-Fi and the desktop via network cable to the Comtrend AR-5381u. A Windows XP ISO with a total size of 590MB has been copied, reaching a peak speed of 13MB / s.

Review Comtrend AR-5381u

Bandwidth between 2 PC’s. A test has been made using the jPerf program to measure the bandwidth between the TOSHIBA and the Desktop.

Review Comtrend AR-5381uTest Scenario # 4

Equipment used: Apple iPhone 2G with Wifi activated and connected to the AR-5381u router. A test has been done through adslnet, it is a Java-based test, since the iPhone does not support flash.

Review Comtrend AR-5381u

It is very clear that if you do not have a device that complies with the IEEE 802.11n standard, the performance will not be the same no matter how much we try.

SAMBA server test

As a novelty and as we have mentioned before, this router has a SAMBA server if we connect any Pendrive or external USB disk. So what we have done has been to map a network drive on our laptop with Wifi from a 500GB disk connected via USB to the router.

Review Comtrend AR-5381u

Then we have taken the same Windows XP ISO located on the disk and we have copied it to our laptop. All via Wireless.

Review Comtrend AR-5381u

As an informative note, the SAMBA server built into the router is not capable of recognizing files larger than 2GB in size. It is possible that in the future with firmware updates (it is a problem of the format of the hard disk identified, presumably the FAT32 driver should be added), this problem will be solved.

Conclusions

For my part, I have come to the conclusion that it is a quite acceptable router given its compact size. Much better hardware has been included than in previous models and that has been noticed in the performance. The tests are more than satisfactory.

About the Wireless problem in this router

The forums are full of complaints about the Wi-Fi of this router, both the Comtrend forum and the Jazztel Technical Support forum, as we discussed in RedesZone a few days ago. I have not had these problems with this model, everything has gone correctly, the tests speak for themselves.

valuation_4