Networks must keep pace with the times: network cabling product upgrades

I. Necessity of network cabling upgrade

Currently, enterprises that have achieved network connection have already connected to the desktop through a 100 m switch to make the entire enterprise span to M. However, as the enterprise scale expands, as well as the increasing number of network multimedia applications, such as voice and video conferencing needs and online video training), the bandwidth requirements for switches and between switches and servers are getting higher and higher, the original bandwidth has become a bottleneck restricting network transmission. Therefore, upgrading the backbone network to gigabit has become the focus of enterprise upgrade. Specifically, the network upgrade will be caused by the following factors.

1. The company's business is expanding, the number of online workstation is increasing, and the network size needs to be expanded, resulting in insufficient bandwidth.

2. increasing network application requirements of enterprises, such as new financial software, data warehouse, ERP, call center, CRM, and e-commerce applications, lead to an increase in concurrent data volumes and sudden operations, challenges the Security and timeliness of the original network.

3. Requirements for network security and network management. To ensure communication and security between different departments, You need to upgrade your network equipment when you need to divide VLANs, isolate broadcast storms, and enhance user management.

Ii. How to Design the upgrade Environment

The transmission speed of Mbit/s between desktop systems is enough to meet the current multimedia applications, and the expansion of desktop systems is enough to stack more Mbit/s switches. Therefore, the upgrade focuses on the upgrade of the backbone network. To upgrade the network trunk to gigabit, change the core switch from the original Fast Ethernet switch to a Gigabit Ethernet switch. The next step is to upgrade the connection between the switch and the server to gigabit, which is what we often call the upgrade of the core layer. Then, the vswitch connected to the core layer should have 1 Gbit/s ports and Mbit/s ports. The vswitch should be connected to the core layer switch with 1 Gbit/s ports and Mbit/s connections to the desktop, of course, for environments with high network requirements, the speed from desktop to desktop can also be Gigabit. We can consider the following factors when designing the environment:

1. Make the server have Gigabit capability

In the current mainstream C/S Client/Server) mode, the increase in server requirements after the network application upgrade is the most obvious. Therefore, you must first make the server have gigabit network service capabilities, even if the connection speed between the server and the enterprise's core network device reaches 1 Gigabit, two factors need to be considered: the network cable and the network card. The network cable can use cat5e or cat-5e twisted pair wires. Both of them support gigabit connections and are relatively low in cost. Therefore, try to select the NIC of the twisted pair port for the server to save investment.

When the application requirements are increased, the original server is often difficult to meet the heavy network access requirements, but completely replacing the server is not economical. Therefore, server cluster or Server Load balancer technology should also be used to organically organize new servers and original servers to share heavy network service tasks, server redundancy can also be achieved in environments with high stability requirements.

Note: In the network, 80% of the access traffic is for the server, so most of the data traffic to the server needs to be transmitted through the backbone network. Even gigabit connections cannot meet the requirements. In this case, we can consider the use of optical fiber aggregation technology to bind multiple gigabit connections together, increasing the bandwidth of backbone connections exponentially to meet network needs.

2. network backbone upgrade

To upgrade a Fast Ethernet to a Gigabit Ethernet, you should first consider upgrading the core switch, of course, using a Gigabit Ethernet switch such as the Cisco Catalyst 4000 Series or the Catalyst 6500 series ). Then, upgrade the backbone switch. The backbone switch must have a gigabit port. Different backbone switches can have a gigabit port, for example, Cisco Catalyst 3550-12G ), it can also be connected to a core switch using a gigabit port and a desktop system using a 10-Gigabit port, for example, Cisco Catalyst 3550-24-EMI ).

3. Upgrade other network devices

Considering cost saving and practical application needs, connecting desktop and IP Phone terminal devices usually uses MB access, which can protect the investment of most EDGE network cables, it can also downgrade the original MB backbone switch to an edge switch. Therefore, the edge switches are basically asymmetric switches, that is, they have 1-2 Gigabit ports connected to the core or backbone switches, and m ports connected to the desktop, therefore, when designing a 10-Gigabit network, you need to consider that the switch should have the module upgrade function to prepare for the upgrade to gigabit later. However, the desktop has almost no need to make any adjustments for smooth upgrades.

Iii. precautions during upgrade

1. system redundancy

If a problem occurs in the backbone network equipment of a gigabit network, it will paralyze the entire enterprise network. Therefore, we need to consider the stability of the backbone network equipment, therefore, when purchasing a device, you should give priority to devices with easy capabilities. You can consider using dual NICs on the server for network redundancy. Many companies have this function for NICs, for example, Intel's Gigabit Server Nic Express Pro 1000 Server Adapter, which has its unique AFTAdapter Fault Tolerance) is the network Adapter Fault Tolerance function. The two NICs on the Server can be set to backup each other, when the network adapter, network cable, and switch port in any link in the link between the server and the switch fail, the other link starts automatically to ensure uninterrupted network operation, AFT technology supports NETWARE and windows nt kernel network operating systems.

If there is a gigabit switch in the network, you can also consider using dual-nic redundancy. As mentioned above, Intel's Gigabit dual-nic can be used together with Intel's ExpressGigabitSwitch to use the Spanning Tree connection, connect two NICs in the server to the two switches, and form a backup relationship between the trunk switches. When any switch fails, the network can still run normally.

TIPS:

The connection method of a vswitch. there are usually two ways to connect a vswitch: Chrysanthemum and star.

The so-called chrysanthemum chain is to connect the switches one by one, and each switch is connected only to its adjacent switches. In this connection mode, the more switches that are stacked, the more requests that need to be forwarded during communication. Multiple Data Forwarding takes up the bandwidth of each vswitch, and may cause the stacked port to become a transmission bottleneck, affecting the transmission rate. In addition, because all switches have only one link, as long as any one of the switches, connected ports or cascade cables fails, the entire network communication may be interrupted. If this type of connection is used, a cable can be connected to the vswitch at the beginning and end as link redundancy. In this way, when a vswitch fails, the Redundant cable is activated immediately, improving the network stability.

A Star Connection uses a switch with multiple Gigabit ports as the stack center. Other switches are connected to the switch through the stack module. This connection mode does not affect the entire network if the cascade port or cable of a single switch is damaged. However, if the switch of the stack center is damaged, the entire system is paralyzed. However, when the performance of the stack center switch is high, the stacking efficiency is higher.

2. system expansion capability

When the backbone network reaches Gigabit, it does not mean that we need to consider the expansion capability of the system. If the gigabit network is not changed, the edge network may also be upgraded in a short time, when the number of desktop hosts increases, edge switches may be upgraded. Therefore, we need to consider the expansion capability of the edge switch when designing the entire system upgrade. Therefore, when purchasing devices, you need to consider purchasing devices with strong stack capabilities, such as Intel 510T series vswitches that can be expanded and stacked, with a specially designed matrix stack module MSM1000M, a maximum of seven switches can be stacked together, and each stack can form up to 196 10/100 M access ports. The connection bandwidth of the switch in the stack is 2.1G, which can avoid the bottleneck caused by the M twisted pair connection of the traditional switch. The total bandwidth of each stack is 16.8 GB, And the throughput is 5.6 GB.

3. Distance of Integrated Wiring

Because the backbone network is a gigabit network, the requirements for cabling are high. A slight carelessness may lead to a sharp decrease in the network connection speed. For long-distance cabling, such as inter-building cabling, multi-mode optical fiber or single-mode optical fiber is usually used. Because the single-mode optical fiber can well support Gigabit Ethernet, the effective transmission distance of 1000Base-LX is 2 km. If you use the initial wiring, we recommend that you use it. However, if multi-mode optical fiber is already used in the original wiring, it should be carefully confirmed. The transmission distance of the multimode optical fiber of 62.5/125 μM is 220 m, and the transmission distance of the 50/125 μm multimode optical fiber is 550 m. When the above distance is exceeded, you should consider adding a zoom-in device or re-wiring the device.

If the maximum distance of the core switch is 100 m, you can use the original cat5e or cat6 cabling system to connect to a gigabit network with a 1000Base-T device, which has the lowest overhead. Multi-mode optical fiber is recommended in the vertical wiring system, and six unshielded twisted pair wires are selected in the horizontal wiring system. It should be noted that although the five types of cables also support Gigabit bandwidth, the total cost of the equipment will increase, but it is better to re-lay the cat-5e or cat6 cables, which is more economical.

4. make overall planning before upgrading

Before upgrading the network, you must make overall planning and design. First, you must determine the backboard bandwidth and data throughput required by the core switch based on the application to meet the current needs of large data forwarding and routing, at the same time, a certain amount of rich space should be available to avoid updating devices due to insufficient service capabilities when application requirements are improved in the future. servers should be able to implement or possess cluster service capabilities, the ability to share load and redundancy can improve the response speed to data requests, reduce the waiting time of customers, and ensure the stability of the entire system. Multiple links should be established between the backbone switch and the central switch, achieve load balancing and redundancy.

Summary:

When considering the overall upgrade, we need to prioritize several metrics. First, system reliability. Because the core network is the core structure of the entire enterprise network, its importance is self-evident. Once paralyzed, it will have a huge impact. Therefore, reliability should be the first priority for such devices and lines, regardless of brand selection or device configuration. The second performance should be the core network node, core switches and aggregation switches must be able to provide fully non-blocking multi-layer switching performance. Third, the manageability of a network directly affects the operating costs and quality. Therefore, all nodes should be manageable, and the network management system should be as concise and practical as possible, so as to comprehensively monitor and manage network business traffic and operating conditions; fourth, scalability. This is especially evident in edge switches. It requires stronger stacking capabilities and can be easily resized. Fourth, security issues are equally important in local networks. In addition to core switches, desktop access switches, and aggregation layer switches, security issues should also be considered, such as Access Control and bandwidth control, control the infringement of poor services on the entire backbone network.