THIS IS NOT AN OFFICIAL DOCUMENT OF THE UNIVERSITY OF BIRMINGHAM OR THE SCHOOL OF COMPUTER SCIENCE. NEITHER THE UNIVERSITY NOR THE SCHOOL HAS ENDORSED THE OPINIONS EXPRESSED HERE.
Some tests demonstrating the serious consequences of not having a QoS option in the
SuperHub router subsystem, with a strong recommendation to switch to 'modem' mode
with a separate router, can be found here.
In return for my money they sent me a package containing The Superhub, some cables, a spanner and some documentation, promising that this would replace my existing (old, restricted) cable modem and wireless/ethernet router (Dlink model DIR 615), both previously provided free as part of the broadband package.
I soon found that the "killer" claim on their blurb
The Super Hub is available exclusively to Virgin Media customers, and has been custom-made to provide you with killer performance and wonderful ease of use.had an interpretation (i.e. performance killer) quite different from the one intended. I later found out that very many users were complaining on the VM on-line forum (to their credit, VM support that, and some of their knowledgeable staff take part in the discussions): http://community.virginmedia.com/
People who have problems with the superhub and land here searching for solutions may find the above link to the forum useful.
Unfortunately the 'tree-structured' organisation of the forum and the lack of an analytical table of contents, together with the large numbers of users writing in with problems, suggestions, questions, etc. can make it difficult to find the most helpful information. There is a search facility, but no advice to try it first, with examples. When there are hundreds of messages reporting problems and some reporting solutions it is not reasonable to expect users to scan through all the previous postings.
A much better structure is needed, including a warning to people to try searching first before they post.
What's the superub?
The SuperHub is apparently made by Netgear to Virgin Media's specification (which unfortunately seems to have given more attention to superficial appearance than to performance, like the "headlines" in New Scientist...).
They have promised a firmware upgrade for the superhub that will remedy some of the deficiencies, but by May 30th 2011 there are still complaints pouring in, even after the first firmware upgrade.
One of the problems I and others found was seriously inadequate wireless reach compared with the older Dlink device, so I did what several others have done, namely disable the wireless capabilities of the Superhub connect the Dlink to it configured to treat the Superhub as a service provider source, then connect our desktop PCs and wireless laptop to the Dlink.
Unfortunately, in that configuration the Dlink cannot make use of the "Dynamic DNS" feature, which I and others had found very useful, i.e. enabling it to have a constant internet url despite changing IP address. (Perhaps VM will manage to include that in the promised firmware upgrade for the Superhub.)
My superhub is now just functioning well as a mere cable modem, though I can use its ethernet ports if needed. Because it sits "edge-on" on my shelf (so that I can see the status lights easily) it takes up far too much space and looks truly awful, because VM/Netgear designed all the cable sockets and the power socket to be on one of the flat sides rather than the opposite edge to the status lights -- as other hubs do.
That problem was reduced after I transferred the router function to the old Dlink, leaving the Superhub only with power cable, incoming broadband cable, and one ethernet cable connected to the dlink. It still looks messy, however.
---------------------------------------------------------------------------------------------------------------------------I think the superhub was originally designed not as a hub but as a Virgin advertising device, because the flat face has the glowing Virgin logo, which I expect will be of no interest to most users. Not even as a work of art.
Update 18 Sep 2011: Superhub Firmware Release 30 supports modem-only mode
A few days ago I had to shutdown and then switch on my superhub. As a result it was automatically upgraded to firmware revision 30, which included an option to make it operate only as a cable modem, as requested by many disgruntled users on the VirginMedia community forum.A description (not by me) of what I had to do before the modem-only option can be found here:
That allowed me to reconfigure the Dlink DIR-615 Router as it was intended to be used when connected with a cable modem. It now gets its external address and DNS addresses directly from the service provider and more importantly I can now also use the DDNS (Dynamic DNS) facility provided by Dlink, so that it can always be accessed by the same URL even though the IP address changes from time to time.
I found that in order to get maximum wireless performance (up to about 31Mb/second for downloads) I had to set the router's wireless configuration using the 'manual' option to use security mode "AUTO(TKIP/AES) rather than simply "TKIP". This allows newer wireless cards to use the full available speed while older ones (as in a six year old Dell latitude D610) run more slowly (e.g. up to about 25Mb/sec).
Warning: make sure you remove all dhcp settings from the superhub except what is required for the router to connect. It is probably best to use static IP addresses for that purpose.
My superhub has 192.168.0.1 (and also the non-configurable address 192.168.100.1).
In that configuration, the Dlink router had 192.168.0.2 for access from my machines, and 192.168.0.3 as external ip address, used by the Superhub to connect to it.
Warning: I don't know if the instructions on that file work since the firmware on the superhub was upgraded. I used that configuration with Superhub Firmware R25.
(For a long time I did not power down my Superhub, in case that caused the firmware to be automatically updated. I did not want to take any chances with Virgin Media's 'experimental' revisions.)
So now the Superhub works as a bulky, messy (because wires come out of the side) and probably unnecessarily power hungry cable modem, much bigger than my previous cable modem. But at least it works, at last, by doing very little.
SSH Timeouts on the Superhub (Before conversion to modem only
I found I had frequent time-outs when using SSH, as reported, with a solution here: here.
These are the main details from that file:
After wasting time on a long phone conversation with a member of VirginMedia technical support staff, in some unknown country, who had great difficulty understanding the problem because he apparently had never heard of SSH, or logging through to another machine (I wonder how much that conversation cost VM?), I consulted colleagues and the internet. I discovered that there are several web sites where users of internet services complain about hubs that cause SSH connections to time out (although this never happened to me before I upgraded to Superhub -- so the old 20Mb/s VM cable model had a more sensible design). The Superhub URGENTLY needs an option enabling users to adjust time-out periods for inactive connections: the current default seems to be a few minutes, which is quite intolerable. (From complaints on the VirginMedia community forum it seems they have not fixed this in their first firmware revision R26). For linux users like me, the solution is either to expand the 'ssh' command using flags something like these (where the numbers refer to seconds) -o ServerAliveCountMax=1000 -o ServerAliveInterval=10 or else (preferaly) in your linux computer's SSH configuration file ~/.ssh/config add something like this # Site-wide defaults for various options Host * ServerAliveCountMax 600 ServerAliveInterval 10 I expect Mac users have a similar option. I haven't a clue what a Windows user would have to do, as I never use MS windows for my work, for reasons given here. If a windows user wishes to post a solution to me by email I'll put it here. Putting stuff on the virgin media forum is mostly useless because they don't have a format that encourages contributors either to search for information or to provide information in a form that helps searchers. If the solution to time out on windows using superhub is here, google will find it.
My early posting in the Features Feedback Thread
SuperHub (VMDG480) Features Feedback Thread (Page 8)
tested dlink router with Superhub as cable modem Options on 17-02-2011 06:53 Superhub vs Dlink Wireless comparisonAfter being told, in another thread, that I had to have the superhub in a specific orientation for wireless to work (which I don't believe) I did some tests and found that wireless speeds close to Superhub are very good (download around 30Mb/s upload around 1Mb/s), but as I move around the house the speeds drop off a lot and in some places I lose the wireless connection completely. Using ping between laptop and desktop, I found less than 0.7ms close to the superhub, but as I took my laptop downstairs it went over a millisecond and going into other rooms it could deteriorate to tens or hundreds of milliseconds then freeze completely. So Superhub is not as impressive as I thought, and moving it around on the shelf, changing its orientation and even tilting it to face downwards while I tested it on the floor below, seemed to make no difference. I decided to try the dlink router previously provided by VirginMedia (DIR-615), which I still have. Previously it was used for the 20Mb/s connection. So I followed instructions posted earlier to convert the superhub to a cable modem (turn off wireless on Superhub, connect router via cable, using DMZ, and a few other things I'll expand later). Results: The wireless performance of the Dlink completely puts the Superhub (Netgear) in the shade. I can now walk all round the house with ping left on and it varies between about 0.6ms and 2 or 3 ms. Moreover, in parts of the house where the connection froze completely with the superhub the wireless connection with dlink still works well and the download test did over 20Mb/s. When the laptop is close to the router, the dlink is marginally slower in download (just below 30Mbs) but it doesn't drop much below that while I move around, whereas download speed on the netgear, as with ping, drops away rapidly as I move further away on the floor below. So, despite preferring to have only one device working rather than two, I'll leave the wireless disabled on the Superhub and put up with the extra cables, etc. required to have the Dlink handling wireless. I've left the firewall on on the superhub. It doesn't seem to affect speed much. Some more DRAFT information about the setting up process is here. At first I had trouble because I left some dhcp reservations on the Superhub that had been used while it was also functioning as a router. But since I removed those reservations it has worked very well as a cable modem. The main missing functionality is not giving the router the external IP address, so that dynamic DNS does not work. I assume that will change when the Superhub gets new firmware. I presume that cannot fix the dreadful wireless performance (except at very close range). If VM ever offer a version of the Superhub that (a) has wireless hardware capable of matching the DLINK-615 and (b) has firmware providig a very much better range of facilities and user interface than the current horrible mess, I'll consider switching: I would rather have one device than two on the end of my VM cable: the ONLY good feature of the superhub in my experience. I hope this information is of use to both Virgin Media and customers who have switched or are thinking of switching to superhub. I assume no firmware change is going to help the Superhub overcome this serious limitation in wireless performance, so I would recommend anyone upgrading above 20Mb/s to hang on to your wireless router, if it is any good.
At least VM are consulting about the firmware upgrade -- a bit late after failing to do proper requirements analysis before choosing a solution, a performance-killer (as their own description so nearly puts it) solution as far as wireless is concerned. But in my case the upload and download speeds of the cable-modem portion are what I expected for my package 30Mb/s download, and 1Mb/s upload (later to be expanded to 3Mb/s).
Some of the VM packages involving the Superhub include a USB Wireless N dongle. This is not true of the upgrade to 20Mb/s.
VM charge an additional £30 for the dongle.
However there are plenty of well reviewed wireless dongles available from Amazon and others, including a very cheap Edimax which worked well when I tried it.
Edimax EW7711UTn USB wireless receiver This tiny but fully functional device is available for only 10.99. For details, including reviews see the Amazon web site http://www.amazon.co.uk/Edimax-Ew-7711utn-150Mbps-Mini-size-Adapter/dp/B001UE6OU I bought one to try as an alternative to a cable connection for my wife's PC running windows XP. It is in one of the most difficult parts of the house for wireless connection to our DLINK-615 router. In fact the Edimax worked, but with a noticeable reduction in speed compared with cable. However, when I added a 2 meter USB cable and suspended it from a curtain rail the performance ws very close to the cable. I suspect the slightly more version of Edimax with its own aerial attached might have worked better without the USB cable. Update 18 Sep 2011 I have now tried it on a PC running Fedora 15. As explained in http://www.cs.bham.ac.uk/~axs/laptop/#edimax a driver package was available from one of the standard Fedora repositories. The Edimax works very well on both Windows and Linux (at least with Fedora 15). On XP the installation process worked fine, and the user interface that comes with it is better than the default interface Windows provides for wireless connections (even on Win7). But the role of profiles (to remember keys/passwords) is not obvious at first. There are several other low cost USB wireless receivers. Alternatively you can buy one from Virgin Media for £s; 30. I don't think I would trust them provide a good wireless device, after seeing the wireless performance of the Superhub.
School of Computer Science
The University of Birmingham