Bsit Gen300 Final

Getting From Here to There: The Career Value of a College Education

GEN/300

My present career is in Information Technology for a regional company. I work as a Senior Network Analyst in the Information Services Department, and provide support for all devices on the computer network. I work on a team of seven members with responsibility for over 400 file servers, 40 routers, and 120 switches at more than 60 locations. Our company runs a mixture of network operating systems including Netware 6, Windows 2000 server, AIX, and various flavors of Linux.

I provide second level support for file servers, network operating system, user administration, data backup, clustering, directory services, file permissions, and virtual tape libraries. I determine hardware standards, negotiate support contracts, and renew maintenance agreements for our network equipment. I wear many hats in the company, and it certainly keeps things very interesting and fast paced.

My primary job is to provide support for our company's storage area network (SAN). The SAN infrastructure includes fibre channel switches and adapters, disk subsystems, storage appliances, and management devices. The SAN provides external storage to our corporate file servers. It is also used to maintain a mirror of critical data to a disaster recovery site. According to Webopedia, "data mirroring is the act of copying data from one location to a storage device in real time." (Anonymous, n.d.). ]

A director appliance is a high-powered file server that controls the disk resources connected to the SAN. The director runs the Linux operating system with a proprietary application to manage the disk subsystem. Clients must be defined through the director's administration interface in order to gain access to disk resources on the SAN.

Data mirroring is also accomplished by using a director appliance. According to Kai Lamb (2004), upon initial creation of a mirror:

The primary and mirrored disks are synchronized to match data on both sides. This process is driven by the (appliance) software and does not involve the application server. After the synchronization is complete, all write-requests from the associated application server are delivered simultaneously by the appliance to both sides of the mirror. It is important to realize that the dual-write process is controlled at the appliance, not at the application server. With this design, only a single I/O request needs to traverse the front-end of the storage network, thereby eliminating the extra storage traffic created by host-based mirroring as well as relieving the host CPU from having to process dual write commands.

Data mirroring is often employed for disaster recovery purposes. The SAN disks are placed in two different geographic locations that are linked together via the company network and a data mirror is established between the two sites. The secondary site provides the SAN disk resources in the event that a physical disaster occurs at the primary site.

All devices on the SAN are interconnected via a fibre channel network. Each device contains a fibre channel interface that is connected to a fibre channel switch. The fibre channel switch acts as a port concentrator. It allows or restricts conversations between devices on the fibre channel network through a process called zoning. Administration of a fibre channel network is minimal after the initial implementation. Troubleshooting fibre channel connectivity and performance problems can be extremely tricky.

I also provide support for ethernet switches, routers, and dense wave division multiplexers. These devices provide network connectivity at various different levels using copper or fiber optic cabling.

Ethernet switches are used in local area networks. They provide connectivity for end user computers, file servers, printers, and scanners. Ethernet switches allow these resources to be shared by other devices and users that are connected to the same network.

Routers are devices that connect several local or wide area networks together. They act like traffic cops for any data packet that has a destination on a remote network. Routers can also be used to segment networks, connect multiple networks of dissimilar topologies, or to provide internet access for an entire corporation.

Routers normally contain multiple interface ports. Each network or circuit being connected to a router requires a dedicated interface.

My responsibility also includes installation and configuration of dense wave division multiplexers. "Dense wave division multiplexing (DWDM) is a fiber-optic transmission technique that combines multiple optical signals so that they can be amplified as a group and transported over a single fiber to increase capacity." (International Engineering Consortium, 2004).

DWDM technology can also be used to extend signals such as fibre channel, SONET, or serial over extremely long distances. The dense wave signal can travel beyond the specified distance limit of many of the native transports. The performance and reliability of the signals are maintained to the same degree as if the signals were being transmitted over short distances. Our company uses DWDM to connect mainframe devices, tape drives, and fibre channel switches to remote devices at a distance of greater than 50 miles.

Dense wave equipment is often very difficult to troubleshoot. The optical lasers are only tolerant within a range of a few decibels. A fingerprint or piece of dust on the end of a connector can cause enough attenuation to degrade a signal below its acceptable threshold. The equipment runs at a very high temperature, so it is also prone to heat related failures.

Two technicians are usually required to troubleshoot dense wave problems, as the connecting pieces of equipment are normally placed many miles away from each other.

I am currently working on a project to implement a wireless communications network for our company's electric substations. Each substation has an automated meter reader (AMR) data collection unit that sends information to a central database. The AMR units are located in 250 remote substations, and the central database is located in the corporate data center. The existing system uses cellular modems and leased lines to connect the AMR units to the central database. Implementation of a wireless network will cost $250,000, and will allow the existing circuits to be disconnected. This project will save the company over $1,000,000 annually after it is implemented.

I am also working on the design of a new outage management system for tracking our electric and