Monday, August 2, 2010

SAD 2 Assignment 3

Computer hard and software are the components that comprise the computer network. These are maintained by a network specialist. Since our university has a system that is networked, we have a network specialist that responsible for the network design and security. He has to insure the system condition, network connectivity throughout the university’s system infrastructure. Network specialist is focused more particularly on troubleshooting and/or debugging network related problems.

Now, since we have to examine the system deployed in our university knowledge on networking is indeed what we need. So, we arranged an interview with our network administrator and/or a network specialist. Engr. Ariel Reyes. Unfortunately, due to his tight schedule we were not able to conduct interview and discuss with him our questions and concerns. With that, we were able to create and formulate questions that we want to know. Below are the questions that had been forwarded to the network specialist.



Q and A:

1. In system development, how various parts of the system communicate with each other throughout the university? In what way?

 Regarding System Development, the best person to ask is our University Programmers, Mr. Fortich and Dr. Mercado.

2. What are the components involved in the system(s) in the university? (hardware, software, technology, etc.)

• I am not in the right position to discuss the details of the software components used as there are other assigned personnel for such job. However, talking about hardware component and technology used, basically I, assigned as the network administrator, is entrusted to maintain our different servers to run 24/7. Currently, we have our Web Server hosted here in our University in our HP ProLiant ML350 Server. Its an old but stable server set-up here in our Networks Office and has been active since Engr. Val A. Quimno , not yet a dean, was appointed as the Network Administrator. The said server has the following specification:

• Intel Xeon 3.0 GHz, 3.2 GHz, or 3.4 GHz processors (dual processor capability) with 1MB level 2 cache standard. Processors include support for Hyper-Threading and Extended Memory 64 Technology (EM64T)
• Intel® E7520 chipset
• 800-MHz Front Side Bus
• Integrated Dual Channel Ultra320 SCSI Adapter
• Smart Array 641 Controller (standard in Array Models only)
• NC7761 PCI Gigabit NIC (embedded)
• Up to 1 GB of PC2700 DDR SDRAM with Advanced ECC capabilities (Expandable to 8 GB)
• Six expansion slots: one 64-bit/133-MHz PCI-X, two 64-bit/100-MHz PCI-X, one 64-bit/66-MHz PCI-X, one x4 PCI-Express, and one x8 PCI-Express
• New HP Power Regulator for ProLiant delivering server level, policy based power management with industry leading energy efficiency and savings on system power and cooling costs
• Three USB ports: 1 front, 1 internal, 1 rear
• Support for Ultra320 SCSI hard drives (six hot plug or four non-hot plug drives supported standard, model dependent)
• Internalstorage capacity of up to 1.8TB; 2.4TB with optional 2-bay hot plug SCSI drive
• 725W Hot-Plug Power Supply (standard, most models); optional 725W Hot-Pluggable Redundant Power Supply (1 1) available. Non hot plug SCSI models include a 460W non-hot plug power supply.
• Tool-free chassis entry and component access
• Support for ROM based setup utility (RBSU) and redundant ROM
• Systems Insight Manager, SmartStart, and Automatic Server Recovery 2 (ASR-2) included
• Protected by HP Services and a worldwide network of resellers and service providers. Three-year Next Business Day, on-site limited global warranty. Certain restrictions and exclusions apply. Pre-Failure Notification on processors, memory, and SCSI hard drives.
Aside from it, our mail server running under Compaq Proliant ML330 Server, our oldest server, is also hosted here in our Networks Office. Together with other Servers, such as Proxy and Enrollment Servers, both proxy and our enrollment servers are running in a microcomputer/personal computers but with higher specifications to act as servers.

REACTION:
As I search the net about the HP ProLiant ML350 Server that is used to the university’s as a server, I learned that this technology is described as DUAL. It has Dual Socket, Dual Core, and Quad Core Intel, Dual-redundant hot plug power supplies, dual redundant fans and the smaller, lighter and quitter dual-purpose chasis and many more. With this specification, this server has a good and flexible server. This kind of server is designed for reliability, expandability, performance and environmental features.

3. How do these communicate with one another? (topology, network connectivity, protocols, etc.) – may include data flow/ UML diagrams to better explain.

 All Servers are connected in a shared medium grouped as one subnetwork. In general, our network follows the extended star topology which is connected to a DUAL WAN Router that serves as the load balancer between our two Internet Service Providers. All other workstations are grouped into different subnetworks as in star topology branching out from our servers subnetwork as in extended star topology. At present, we are making use of class C IP Address for private IP address assignments. Other workstations IP assignments are configured statically (example: laboratories) while others are Dynamic (example: offices). All workstations are connected via our proxy servers that do some basic filtering/firewall to control users access to the internet aside from router filtering/firewall management. So, whenever any workstation has to connect to the internet, it has to pass through software and hardware based firewall.

 REACTION
Since our network is connected with the DUAL WAN Router (which is stated above), I guess it is good to use this technology. This router is for fail over, when one connection is down the other one will automatically pick up and continue the job. And according to my research, using a DUAL WAN Router will add up total bandwidth, with this the throughput or performance in computer network is increased.

4. What are the processes involved in the communication (each system to other systems)?

 As mentioned above, in item 3, all workstations are connected via a proxy server. It means that whenever a workstation is turned on, it requests for an IP address from the proxy server (for dynamically configured IP address) and connect to the network after IP address is acquired. As connection is established, each system can now communicate and share resources within the same subnetwork and to server following the concepts discuss in your Computer Network Class.

5. How do you go along with the maintenance of the system?
 Basically, our servers are expected to be in good condition since it is required to be up 24/7. Daily, during my vacant period, monitoring on the servers are observed that includes checking logs, checking hardware performance such as CPU health, etc. If problems are observed, remedies are then and then applied. Once in a week, regular overall checkup is observed as preventive maintenance to ensure not to experience longer downtime if possible.

 REACTION:

As I mentioned in my introduction, one of the task of the network specialist is to insure the networked system’s condition, with that it needs to have a regular check up on and proper maintenance since some components must run 24/7 such as the servers.

 For maintaining the network system, one good method or practice is to develop a PREVENTIVE MAINTENANCE plan. It refers to performing proactive maintenance in order to prevent possible systems’ problems.

The following are the reasons why should have to develop a PREVENTIVE MAINTENANCE Plan.

Preventive Maintenance Saves Money: Avoiding problems with your PC will save you money in the long run. By preventing a problem from occurring, you will no longer need to spend money on new components or repair jobs.

Preventive Maintenance Saves Time: Preventive maintenance saves time because it saves you the inconvenience and disruption of system failures and lost data. Most preventive maintenance procedures are quite simple compared to troubleshooting and repair procedures.

Preventive Maintenance Helps Safeguard Your Data: For most people, the data on the hard disk is more important than the hardware that houses it. Taking steps to protect this data therefore makes sense, and that is what preventative maintenance is all about.

Preventive Maintenance Improves Performance: Some parts of your system will actually degrade in performance over time, and preventive maintenance will help to improve the speed of your system in these respects.

This will benefit us so as to have secure and steady computer systems.

there are two types of Preventive Maintenance:

Preventive Maintenance
Preventive maintenance is a schedule of planned maintenance actions
aimed at the prevention of breakdowns and failures. The primary goal of
preventive maintenance is to prevent the failure of equipment before it
actually occurs
. It is designed to preserve and enhance equipment
reliability by replacing worn components before they actually fail.
Preventive maintenance activities include equipment checks, partial or
complete overhauls at specified periods, oil changes, lubrication and so
on. In addition, workers can record equipment deterioration so they
know to replace or repair worn parts before they cause system failure.
Recent technological advances in tools for inspection and diagnosis have
enabled even more accurate and effective equipment maintenance. The
ideal preventive maintenance program would prevent all equipment failure
before it occurs.

Value of Preventive Maintenance
There are multiple misconceptions about preventive maintenance. One such
misconception is that PM is unduly costly. This logic dictates that it
would cost more for regularly scheduled downtime and maintenance than it
would normally cost to operate equipment until repair is absolutely
necessary. This may be true for some components; however, one should
compare not only the costs but the long-term benefits and savings
associated with preventive maintenance. Without preventive maintenance,
for example, costs for lost production time from unscheduled equipment
breakdown will be incurred. Also, preventive maintenance will result in
savings due to an increase of effective system service life.

6. Does the system follow a specific standard? Explain Please.

 As I was appointed as the Network Administrator, everything was already in place except for some minor changes. Basically, different networking standards was already observed such as cabling standards, TIA/EIA 568A-B, different IEEE standards as discussed in your Computer Networks Subject, etc.

 We all know that all networking technologies have standards associated with them. One standard used to our system is the TIA/EIA 568B,. It is a set of three telecommunication standards from the telecommunication Industry Association. For structural cabling system ,this standard is used that enable the for its design and structure.

7. How is the security of the system? Are there any vulnerabilities? Risks? Corresponding mitigation techniques? Access control?

 As I have mentioned, we have implemented both software and hardware based filtering/firewall. Basically, Risks or vulnerabilities and different mitigation techniques were considered to increase security in our network. Aside from filtering/firewall, constant monitoring on networks activity also increases the security of the system.

REACTION:

We all know what a firewall is. According to WIKI :
A firewall is a part of a computer system or network that is
designed to block unauthorized access while permitting authorized
communications.
It is a device or set of devices which is configured to
permit or deny computer applications based upon a set of rules and other
criteria.
Firewalls can be implemented in either hardware or software, or a
combination of both. Firewalls are frequently used to prevent
unauthorized Internet users from accessing private networks connected to
the Internet, especially intranets. All messages entering or leaving the intranet pass through the firewall, which examines each message and blocks those that do not meet the specified security criteria.

For HARDWARE firefall, i would like to suggest Adaptive Security Appliance. This is the new product of CISCO in security.One of the advantages of hardware firewalls is the ASIC modules. These
modules perform tasks such as VPN and IPS and relieves the box's main
processor from performing such functions.
Adaptive Security Appliance
CISCO ASA 5500 Series adaptive security appliances are purpose-built solutions that combine best-of-breed security and VPN services with the innovative Cisco Adaptive Identification and Mitigation (AIM) architecture. Designed as a key component of the Cisco Self-Defending Network, the Cisco ASA 5500 Series provides proactive threat defense that stops attacks before they spread through the network, controls network activity and application traffic, and delivers flexible VPN connectivity. The result is a powerful multifunction network security appliance family that provides the security breadth and depth for protecting small and medium-sized business and enterprise networks while reducing the overall deployment and operations costs and complexities associated with providing this new level of security. The Cisco ASA 5500 Series delivers a powerful combination of multiple market-proven technologies in a single Cisco Self-Defending Network is one of the known for Network Security in which the firewall, router and switches play a role in implementing the network security.

8. Are there any interference? During what (most) times do these occur? Explain their effects especially with regards to the business of the university?
 Major Interferences are normally encountered as an effect of unforeseen and beyond our control events such as black outs, and the like. The said interference would of course affect University’s day-to-day businesses for obviously this will paralyze all our activities that rely on electricity and further this might cause damage on our network devices, etc. that may later be the reason for longer downtime. Problems encountered by our providers such as connection to the National/International Gateway also affect University’s business such as correlating to University’s Business Partners outside and within the country.
==these questions were not answered====
9. What are the current trends in network environment ideal for the university?
10. Based on your experience, can you enumerate and discuss your key points for an effective and efficient network environment that is ideal for the university?
11. Can those key points apply to the current trends for the university’s network environment? How it works?
12. Can you draw the general network architecture of the university?
13. On your own opinion, are the users satisfied with the current network setup?
14. What network architecture is used in the university?
15. What are the drawbacks that you found in the existing system? How would you treat these drawbacks?
16. On you own opinion; are there any changes that you want to change in the existing network architecture?
17. How would you see the university few years after implementing the newly developed system?





http://www.nitconnect.net/network_maintenance.shtml
http://en.wikipedia.org/wiki/Cisco_PIX#Performance_specifications

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