Technology trends that can necessitate a LAN upgrade

The biggest headache for IT teams is identifying the trouble spots and knowing how and when to upgrade the underlying infrastructure

Far from the immovable behemoths depicted in the computer science network configuration manuals, today’s LANs are more likely to resemble a fluid mesh of constantly changing connections which demand constant care and attention from the administrators tasked with their upkeep.

But given the legwork and associated downtime involved, the biggest headache for the IT department is identifying the trouble spots and knowing how and when to upgrade the underlying infrastructure.

Many are now putting 10Gbit/s equipment into the core, if not the edge, of their LANs where data traffic bottlenecks between switches and servers are more likely to occur, for example. These upgrades often require amendments to existing cabling, and some organisations are already replacing copper UTP with optical wiring to support both 10Gbit/s now and faster optical bandwidth in the future, especially as the 10Gbase-T standard demands either Cat6A or Cat7 shielded cabling, which often requires an upgrade to existing copper cabling anyway.

Faster Ethernet standards are 40Gbit/s and 100Gbit/s Ethernet over optical wiring, though these include trunking multiple 10GbE or 25Gbit/s ports together and provide the sort of high bandwidth that is not yet widely needed within private LANs, at least outside internal datacentres.

Elsewhere in enterprise LANs, 1Gbit/s and often 100Mbit/s connections provide more than enough bandwidth for linking PCs, printers and other devices to departmental subnets, with companies often choosing to stick with 100BaseT for now to avoid what can be complex and labour-intensive upgrades to cabling where anything less than Cat5 UTP is already in place.

Convergence
Space restrictions and energy-efficiency requirements remain significant challenges for many organisations, especially in datacentres, and this is forcing network administrators to find new ways of consolidating their existing network architecture. This can involve merging multiple legacy voice, data and video networks into a single entity or joining previously separate server and storage networks in the datacentre.

IP telephony and voice over IP (VoIP) technology can now reliably support effective voice communications in the most demanding of business environments, but extensive legacy investment in analogue telephone systems has proved hard to displace in many cases, and the upgrade process is still very much ongoing.

Some companies are also adding video to those networks, not just for videoconferencing and collaboration purposes, but also to replace analogue CCTV systems with pan tilt and zoom (PTZ) digital H.264 cameras that offer higher quality images and more flexible management for surveillance purposes. It should be noted, however, that IP CCTV traffic is deemed so sensitive that it often demands its own subnet to guard against packet loss, latency and other performance problems which can arise if it is mixed with other voice, internet and application traffic on the rest of the Ethernet network.

The more advanced, managed LAN switches also feature various techniques designed to ensure quality of service (QoS) for video traffic, including network admission control, bandwidth reservation, and traffic shaping and prioritisation.

Many IP CCTV cameras rely on Power over Ethernet (PoE) for their electricity supplies, a technology that is tempting some companies into infrastructure upgrades in a bid to counter rising utility bills. PoE ports can deliver up to 13W of electricity to a range of devices over standard UTP cabling, including wireless access points, VoIP handsets and thin clients, while a more powerful 802.3at standard (PoE+) outputs over 25W from each port (though some of that power is dissipated during transmission depending on the distance the charge has to travel).

Power efficiency is also a major driver for datacentre consolidation projects, one attraction of converging Ethernet LANs with Fibre Channel (FC) storage area networks in a bid to reduce the number of switches, FC directors and interface cards needed to route data traffic over both types of network.

Converged network adapters (CNAs) and/or Fabric Adapters (FAs) using the Fibre Channel over Ethernet (FCoE) protocol are designed to offer simultaneous connectivity to a range of LAN, network attached storage (NAS), and SAN equipment at speeds of up to 10Gbit/s initially and eventually reaching 100Gbit/s, and intended to replace the network interface cards (NICs) and host bus adapters (HBAs) previously used for the same purpose on two separate networks.

Network management and IPv6
In many cases, it is a requirement for better network management and reconfiguration that drives administrators to make changes to their LANs, with access security, traffic monitoring and application acceleration all high on the list of improvements required.

Part of that management focus includes IPv6, a protocol that has been supported in router, switches and operating systems for many years, but which has not so far been turned on by the vast majority of administrators. IPv6 extends the range of available IP addresses from a pool of 232 32bit IPv4 addresses to 3.4x1038 128bit IPv6 addresses, allowing an almost infinite number of devices to be connected to the internet with static, rather than dynamic, IP addresses at any one time.

Though mostly concerned with routing network traffic onto the internet via wide area networks (WAN), IPv6 also allows companies to give every server, workstation, PC or other device attached to the LAN its own public IP address without having to use network address translation (NAT), which can cause problems in certain configurations.