With any network-based system, a switch is an integral part of the infrastructure. Traditionally, security manufacturers have shied away from recommending switches, because of fears that if they do so they might then be asked to offer technical support to installers and integrators. Whilst you can understand their point of view, it hasn’t helped those who are migrating to systems that deploy new and emerging technologies. Another option is to seek out a switch which has been optimised for video surveillance applications, such as the DGS-1100-26MP smart switch, available from D-Link.
It seems slightly strange, almost counter-productive, that whilst every networked system will require some type of Ethernet switch, only a handful of the more progressive and forward-thinking security manufacturers are happy to work with installers and integrators when it comes to selecting an appropriate device. It’s a little like a car manufacturer refusing to suggest fuel, oil or tyre choices for their vehicles. If the performance of a security device may be dependent upon the quality and capacity of a specified switch, then surely it makes sense to help ensure that an appropriate unit is deployed?
Of course, you also have to consider how most switch manufacturers address the security market’s needs, and in many cases there is little to no involvement. For many switch manufacturers, their main target is the IT user: businesses and organisations, data centres and householders are all targeted with products that meet their specific networking needs.
While the security industry is also a significant customer, it’s fair to say that the industry has not always presented it needs to the IT manufacturers in a compelling way. The result is that few manufacturers in the IT sector have designed switch ranges with the security market’s needs in mind.
With that said, a growing number of companies from both within and outside of the security sector have recognised the needs of the market, and as a result offer switches that have been optimised to deal with the demands of always-on high bandwidth applications such as video surveillance and site security.
One of these is D-Link, and its Gigabit Ethernet PoE smart switch series – which includes the DGS-1100-26MP featured in this test – offers a range of benefits designed to enhance video surveillance applications.
Specification
The DGS-1100 series of smart switches from D-Link offers managed PoE+ devices which have been optimised for video surveillance. The switches are available with 8 ports plus 2 SFP Gigabit ports (DGS-1100-10MP/MPP) or 24 ports plus 2 combo gigabit ports (DGS-1100-26MP/MPP). The difference between the MP and MPP versions is PoE budget.
Our test unit was the DGS-1100-26MP, which features 24 10/100/1000 Base Ethernet ports with PoE support, plus 2 combo Gigabit ports. The combo ports can be used as either Ethernet or SFP, with a dedicated port for each type of connection. However, they share switch fabric and port number, so while allowing differing connectivity, they cannot both be used simultaneously.
The SFP ports are empty and require an appropriate adaptor which is an optional extra; they are supplied as standard with a push-fit cover.
The unit has a PoE budget of 370W, with a maximum of 30W per channel. There is surge protection of up to 6kV.
Switch capacity is 52Gbps, and the forwarding rate is 38.69Mpps (packets per second). The switch has 16MB flash memory and 1.5MB packet buffer.
The surveillance-specific elements are catered for via the unit’s software. The DGS-1100-26MP includes the Auto Surveillance VLAN (ASV) feature. This allows the switch to identify surveillance-based devices, and these are automatically added to the VLAN. This ensures that if the switch (which can also be used in standard mode) is used for other data traffic, such as a corporate LAN, the surveillance traffic is isolated from this.
Video data is allocated a higher priority, ensuring that other network traffic will not impact on the performance of the surveillance system. The switch features ONVIF device support, which allows it to identify third party surveillance cameras and encoders, making the process relatively straightforward.
The switch features an intuitive browser-based graphical user interface, and this gives a simple-to-understand overview of the network topology.
The switch can also enhance any fault finding processes, as it includes loop detection and cable diagnostics.
The DGS-1100-26MP is supplied with a quick start guide, a CD containing the full manual and the DNA (D-Link Network Assistant) utility. For single switch management, a link via a browser can also be used. The switch also includes a power lead, rack mount brackets and a screw kit.
Installation
The physical installation of the switch is very straightforward, as is typical of such devices. An uplink connection is made to the server being used for control, the cameras and/or encoders (or any other network devices) are added via individual ports and the switch is powered up. There are no additional elements, and the process is very much straightforward was you would expect.
With the connections made and the unit running, you can log into the switch. This can either be done via the unit’s static IP address or using the DNA utility. The latter is designed for managing multiple switches and D-Link recommends using a browser link for a single unit.
Once logged in, a wizard guides you through the basic process of configuring the switch. The first choice is whether you wish to run the switch in standard or surveillance mode. Following that you can change its IP details and set a password.
That is pretty much it. There is a checkbox to disable the wizard; if this isn’t checked you’ll have to repeat the process each time you log in.
Once the very brief wizard process is complete, you are presented with a screen which displays the various icons and colour codes that are used as a part of the system overview screen.
Devices are identified as discovered cameras, discovered NVRs and discovered non-surveillance devices. Connections are shown on a diagram, displaying the port, the connected device and its status. Colour codings indicate whether the port has a device connected but not using PoE, a device connected using PoE or a defective device. It also displays information on uplink ports that are currently connected.
Each port in use has an indication of whether the connected device is 10/100Mbps or 1000Mbps. Hovering the mouse over a port shows information including power usage and IP address. There is also an option to enable or disable PoE, which can be useful to address certain switch foibles – more about that later.
Performance
Once logged in to the switch, you have a number of options which could be helpful for installers and integrators. The default screen is a system overview which gives a graphical display of connections and their status. It auto-refreshes every 30 seconds, and does take a few seconds to populate, as do all of the screens.
Devices identified as surveillance units are added to the ASV, and those identified as ‘other’ are not. At first power-up, all of our ONVIF devices were identified as ‘other’. We worked through the menus but didn’t find an option to tweak this information. We then resorted to the PoE enable/disable buttons.
By powering devices down and then rebooting them, we managed to get all but one of our devices recognised as ONVIF devices. On some occasions this process required a couple of camera reboots to be successful! Just as we decided that the final device was never going to be recognised, another PoE cycle did the trick.
Occasionally, logging into the switch would see various cameras shown as ‘other’, thus creating a requirement for numerous device resets.
When there are issues with the consistency of the specification, it’s easy to point the finger at ONVIF itself, or the way manufacturers implement the spec on their devices, but the DGS-1100-26MP clearly does not consistently recognise compatible ONVIF devices, needing a few attempts to get things right. We did notice that when cycling PoE to get units recognised, the GUI performance was, at times, a little ‘hit and miss’.
Interestingly, from the very start the VMS used during the test recognised all of the attached devices, even when we solely searched for ONVIF units.
Another niggle is that when the switch software timed out, logging back in often resulted in an error message that stated, ‘Reach max login number’. This was despite the server being the only device logging in to the server. The only solution was to give up for a period of time!
Most installers and integrators will deploy the DGS-1100 series in surveillance mode. However, should anything other than basic settings (password, IP address, etc.) need to be changed, the switch needs to be in standard mode. In surveillance mode, most of the screen options give status displays rather than options to set or configure performance.
Putting aside the ONVIF detection function, as a switch the DGS-1100-26MP works well and certainly copes with the loads associated with video surveillance. It’s fair to say that switches are typically very much in the background, and if that’s where the DGS-1100-26MP stays, you won’t have an issue with it.
However, as one of the main selling points is the ability to simply and accurately access real-time camera and encoder status reporting, the switch’s GUI is very much its Achilles Heel.
Verdict
The introduction of ONVIF detection is a new feature for the smart switch range, but it’s not very consistent. All attached devices were at some point correctly recognised, but we never saw all of them recognised without some degree of rebooting. Checking back would see some change from ONVIF to ‘other’ for no reason.
Some of the additional functionality is relatively new, so we would expect to see firmware updates. These should rectify some of the GUI issues.
As a fit-and-forget switch the DGS-1100-26MP does the job. However, one of its main differentiators is the GUI, and we feel that this is an upgrade or two away from being recommended. We’ll let you know if it gets there, because when it does it will be a useful tool for many installers and integrators.
READ THE NETWORK ZONE ARTICLE ON SELECTING A SWITCH FOR SECURITY APPLICATIONS