Nowadays, most of us have either got a or used a wireless network of some description. Whether this is our home broadband or cable internet connection, a hotpot in Starbucks or simply a bluetooth connection on our mobile phone – we’ve used a wireless network.
We’ve all without exception used hard-wired networks – computers that are connected to a physical infrastructure with a network cable.
Networks are part of life, but how can we tell which network type is the best type for hosting our critical validated systems and do these transport mediums have to be qualified?
Wired networks are usually the fastest (still) with most Network Interface Cards (NICs) being capable of 100MB or 1000MB Full Duplex thus providing for high performance and high availability. Wireless networks are not capable of such speeds, however the newly approved Wireless N (802.11n) standard provides for 300MB wireless connections with greater ranges than the older 802.11g network capability.
This does not mean that wireless networks aren’t fast – on the contrary, 300MB is a very fast speed – even for downloading massive files and streaming. But are these networks fast enough to support the business requirements of the modern day?
Wireless security is very secure, for a start a wireless network can be hidden making it invisible to potential intruders, similarly it isn’t possible to actually tap the line; in theory an intruder could “listen” to a copper network whereas this isn’t as easy with a wireless network, wireless also provides filtering such that only permitted wireless stations can be authenticated on the network if they’re physically allow and if they’re using the correct key (WEP, WPA, WPK-PSK, etc.)
But what about documentation and proving their reliability and security? Pharmaceutical companies are using wireless networks left, right and centre – even in production. Wireless Networks are acceptable networks to use in GMP environments, however they must still be qualified and some documentary evidence should exist to prove that the cGMP machines performing process operations are able to communicate with the access points in range within the specification of the wireless network’s capability.
Access Point Communication
Consider the published range of a wireless access point being advertised at 90m and that AP (Access Point) is deployed to a production area with 15 vessels in the room, no less than 10 full of product at any one time – this would dramatically impact the communications ability of the AP to be able to speak with the controlling computer; this coupled with additional support in walls and ceilings by reinforced metal will definately impede communications and even purge any chances to robust comms.
So would this make hard wired installations easier? Not necessarily. The addition of bridged APs would help and depending on the availability of accessible ingress and egress routes however being confronted with wireless design issues doesn’t automatically mean that wired solutions are the best.
Wired networks are sometimes cheaper to design and implement, however given the environmental constraints of accessing some rooms, in particular cleanrooms wireless may well be the most viable option. To install a copper cable is usually just a case of telling the cabling contractor where the point should go, however in order for him to install the cable’s containment a safe route must be available, often across many false ceilings – the result can sometimes be a nightmare and sometimes erecting the scaffolding is the most expensive part of the job.
Similarly, wireless networks need to plug into the “the network” at some point so in the event that points are required in an awkward area the exploration of a wireless solution shouldn’t be ruled out. If the equipment doesn’t support wireless than it can often be swapped with something that can, for example in a production area where some scales are required to be linked to network, for say an MES – the scales might have an ethernet port; a solution would be to connect the associated PC to the network via a wireless NIC and then let the scales use the PCs old ethernet port.
Go for a Walk and Save Money
Nothing is like a good old area-walkdown to see what is there, and what is not – all of this can save time and money, whichever route is chosen, be warned network equipment is not cheap therefore the architecture must be right first time. If in doubt contact an expert to conduct a survey of the area and make sure that the chosen route will result in comms.