Technology Toolkit

A CPU, or central processing unit, is the brains of the electronic system it controls. The most familiar system also called microprocessors are found in desktop and laptop personal computers, yet millions of processing chips are also used in what we call embedded applications.

These control units are programmable. In other words they can be programmed to execute a range of instructions, to perform arithmetic and logical operations on data, and control input/output of data. This makes PC very versatile.

They may as we see in the familiar example of PCs run lots of different programs. They may also be programmed to perform the specific functions required in a range of different types of electronic equipment, ranging from consumer electronics for the home to mobile devices to enterprise IT equipment for the data center.

Embedded unit may be combined with other circuitry to create a system on a chip (SoC) solution. For example the chips used to power mobile phones, network switching equipment and hard disk drive controllers all incorporate CPUs that are embedded in SoC solutions.

A computer is typically the fastest running and most advanced component in any SoC. Because it is programmable, the processing unit can be called upon to perform a wide range of tasks. Often these include tasks that were not considered or did not exist when the product was originally designed.

Optimized for low power consumption and high performance, CPU technology is embedded in system on a chip (SoC) solutions that go into many of the most widely used smart phones, set top boxes, disk drives, routers and switches.

As one of a few select companies to hold a full ARM architecture license, Marvell is strongly positioned to leverage the pervasiveness of the ARM architecture.

The processing systems that power our PCs are good at what they do, but they consume a lot of energy and put out a lot of heat. So the battery life of a laptop PC, for example, is limited to a few hours. And the size of a laptop PC is to some extent dictated by the need for heat dissipation.

Just as one architectural approach to processing unit design is dominant in the PC world, another known as the ARM instruction set compliant approach is dominant in the world of embedded CPUs. Over 80 percent of all high performance PC in the embedded world is ARM instruction set compliant.

One major function of system architecture is to define the types of instructions that software programs can pass to the central processing chip. The architecture also defines various other aspects that enable software to work with the main chip. This is a difference between CPU architecture versus micro architecture.

For most people these days technology is almost a throwaway fact of life; for some however old or no longer necessary technology provides a welcome source of additional income.

There can be no better illustration of this than EBay, the auction website. However there are inherent risks that can lead to problems which can only be solved by the use of expert Computer Forensics techniques.

It is important to understand that simply deleting information from a computer hard drive does not necessarily get rid of it; deleting it simply frees up the space so it can be overwritten with new data.

And just as Computer Forensics Experts can retrieve this data should the need arise so too can the well informed and increasingly sophisticated computer criminal.

One of the most common problems found by Computer Forensics personnel is the problem of hard drives not being properly formatted and wiped clean of all or any previous data. Without proper handling these hard drives, often sold on auction websites for a fraction of their original cost, can be reconstituted thus giving rise to identity theft and thus needing the help of an expert in the fight against Computer Crime.

It is of course not just individuals who sell their equipment on auction websites; companies also sell their unwanted equipment in the hope of making some extra money and without considering the consequences of not ensuring their hard drives are properly cleaned.

The home user wishing to make some extra money, or indeed the business user looking to recoup some money spent on newer equipment, can use disc wiping or erasing utilities which can be purchased from reputable Internet sites or from high street retailers but unfortunately many do not engage in this practice and as a result in recent years thousands of private citizen’s details including their dates of birth, PIN (Personal Identification Numbers) and other personal details have been recovered on supposedly clean hard drives.

Computer Forensics Experts are often called upon to help recall lost data and also to prove that data has existed on a particular hard drive at some time.

Unless the hard drive has been removed physically from the computer and replaced with a new one, or the disc has been subject to an erasing utility, the likelihood is the information will be retrievable.

If you are a business and have a large number of computers to dispose of it is wise to take advice from an expert who will be able to help ensure that all personal and sensitive data is removed and non-retrievable before you part company with your computer equipment.

Data deduplication or Single Instancing essentially refers to the elimination of redundant data. In the deduplication process, duplicate data is deleted, leaving only one copy (single instance) of the data to be stored. However, indexing of all data is still retained should that data ever be required.

Example
A typical email system might contain 100 instances of the same 1 MB file attachment. If the email platform is backed up or archived, all 100 instances are saved, requiring 100 MB storage space. With data deduplication, only one instance of the attachment is actually stored; each subsequent instance is just referenced back to the one saved copy reducing storage and bandwidth demand to only 1 MB.

Technological Classification
The practical benefits of this technology depend upon various factors like -
1. Point of Application – Source Vs Target
2. Time of Application – Inline vs Post-Process
3. Granularity – File vs Sub-File level
4. Algorithm – Fixed size blocks Vs Variable length data segments.

Target Vs Source based Deduplication
Target based deduplication acts on the target data storage media. In this case the client is unmodified and not aware of any deduplication. The deduplication engine can embedded in the hardware array, which can be used as NAS/SAN device with deduplication capabilities. Alternatively it can also be offered as an independent software or hardware appliance which acts as intermediary between backup server and storage arrays. In both cases it improves only the storage utilization.

Target Vs Source Deduplication
On the contrary Source based deduplication acts on the data at the source before it’s moved. A deduplication aware backup agent is installed on the client which backs up only unique data. The result is improved bandwidth and storage utilization. But, this imposes additional computational load on the backup client.

Inline Vs Post-process Deduplication
In target based deduplication, the deduplication engine can either process data for duplicates in real time (i.e. as and when its send to target) or after its been stored in the target storage.

The former is called inline deduplication. The obvious advantages are -
1. Increase in overall efficiency as data is only passed and processed once
2. The processed data is instantaneously available for post storage processes like recovery and replication reducing the RPO and RTO window.

the disadvantages are -
1. Decrease in write throughput
2. Extent of deduplication is less – Only fixed-length block deduplication approach can be use

The inline deduplication only processed incoming raw blocks and does not have any knowledge of the files or file-structure. This forces it to use the fixed-length block approach (discussed in details later).

Inline Vs Post Process Deduplication
The post-process deduplication asynchronously acts on the stored data. And has an exact opposite effect on advantages and disadvantages of the inline deduplication listed above.

File vs Sub-file Level Deduplication
The duplicate removal algorithm can be applied on full file or sub-file levels. Full file level duplicates can be easily eliminated by calculating single checksum of the complete file data and comparing it against existing checksums of already backed up files. It’s simple and fast, but the extent of deduplication is very less, as it does not address the problem of duplicate content found inside different files or data-sets (e.g. emails).

The sub-file level deduplication technique breaks the file into smaller fixed or variable size blocks, and then uses standard hash based algorithm to find similar blocks.

Fixed-Length Blocks v/s Variable-Length Data Segments
Fixed-length block approach, as the name suggests, divides the files into fixed size length blocks and uses simple checksum (MD5/SHA etc.) based approach to find duplicates. Although it’s possible to look for repeated blocks, the approach provides very limited effectiveness. The reason is that the primary opportunity for data reduction is in finding duplicate blocks in two transmitted datasets that are made up mostly – but not completely – of the same data segments.

Data Sets and Block Alignment
For example, similar data blocks may be present at different offsets in two different datasets. In other words the block boundary of similar data may be different. This is very common when some bytes are inserted in a file, and when the changed file processes again and divides into fixed-length blocks, all blocks appear to have changed.

Therefore, two datasets with a small amount of difference are likely to have very few identical fixed length blocks.

Variable-Length Data Segment technology divides the data stream into variable length data segments using a methodology that can find the same block boundaries in different locations and contexts. This allows the boundaries to “float” within the data stream so that changes in one part of the dataset have little or no impact on the boundaries in other locations of the dataset.

ROI Benefits
Each organization has a capacity to generate data. The extent of savings depends upon – but not directly proportional to – the number of applications or end users generating data.

Overall the deduplication savings depend upon following parameters -
1. No. of applications or end users generating data
2. Total data
3. Daily change in data
4. Type of data (emails/ documents/ media etc.)
5. Backup policy (weekly-full – daily-incremental or daily-full)
6. Retention period (90 days, 1 year etc.)
7. Deduplication technology in place

The actual benefits of deduplication are realized once the same dataset is processed multiple times over a span of time for weekly/daily backups. This is especially true for variable length data segment technology which has a much better capability for dealing with arbitrary byte insertions.

Numbers
While some vendors claim 1:300 ratios of bandwidth/storage saving. Our customer statistics show that, the results are between 1:4 to 1:50 for source based deduplication.

When it works well, electronic mail can be great. It’s difficult to beat electronic mail for everything from staying in touch with family to requesting info from businesses or other organizations.

Need to send out the same message to numerous people? Want to communicate with somebody over world? Transport pics, manuscripts or other data? For swiftness and efficiency, this nearly instant medium is among the most useful devices of modern life.

As long as it’s working well electronic mail is great. You just can’t beat electronic mail for everything from staying in touch with your friends, family or business contacts. It’s swift and instantaneous.

Need to send the same message to all of your contacts? Whether it be a picture a video file or a long report you’ve been working on electronic mail is the way to go. It’s convenient and fast.

But using electronic mail is not without problems. Let’s say you key in the name of a contact and when you send your message it gets bounced back to you, you might not be saying how great electronic mail is, would you? What If your attachments don’t open when you double click on them? That could cause you some grief.

Not to worry, with just a little patience you can readily overcome most of these problems when using electronic mail. I have listed a few of the most common problems people face when using electronic mail and how to get around them.

Problem – My Electronic mail message was returned
This may be the most frustrating of all electronic mail problems. After taking the time to create a message, you click on the send button and consider your task done. But the next thing you know, a message shows up in your in-box with a heading that says your message did not reach the intended recipient.

Solutions

The first thing you want to do is take some simple steps to insure your sending your message to the right address. It’s simple to misspell and address when you’re in a hurry to get your mail out. Also, there may be a discrepancy between whether it’s a com or net address. Another common problem is that the email is no longer valid. To see which of these might be the problem send out several messages with the changes from com to net or with different spelling. If you send out these messages with variations and two get bounced back but one doesn’t then you have solved your problem by the process of elimination.

Sometimes the source of your problem lies with the recipient. If messages to other addresses go through but fail here, try to contact the intended recipient by other means and report the situation.

The cause may range from a temporary problem with the recipient’s server to a switch to another e-mail provider, to a full in box. In this case, simply waiting may be the best recourse. Or a phone call or other communication may be required on your part to obtain the correct e-mail address. If all your messages are being returned, you may have a connection problem.

Problem 2 – you’ve Lost Your Internet Connection

Sometimes a failure to send or receive electronic mail could be attributed to a lost connection with your Internet service provider.

Solutions

If you see a failure to connect or a no response message or have otherwise ascertained that you have failed to connect, double check to make sure there are no physical problems.

First, ascertain that your cables and connections are in place. If you use a dial-up modem, listen to establish it produces the normal high-pitched dialing sound. If not, the trouble could be a loose connection. Locate the phone cord that runs from the back of your computer to the phone jack, and then make certain that each end is plugged in snugly.

If you don’t hear the expected dialing sound, check to make certain your phone cord is undamaged. If it seems haggard, replace it with a new one. Other steps include making sure the line is secured into the right port, and checking the phone jack by securing the cord into another jack. If you hear the dialing sound after any of these steps, you have made a successful connection.

Connection problems might be more common with dial-up modems than with broadband connections, but the latter is also dependent on physical connections. A loose wire or badly connected cable can easily be problematic. Some of the times a glitch happens that can be best handled by repeating portions of the initial set-up process. A simple fix touted by Verizon technical service reps for some DSL (digital subscriber line) customers is to disconnect the three lines from the back of the modem and then reconnect them in a specified order. When this action is taken, the online connection is at once recovered.

If you’re online but keep getting disconnected, the connection loss can be the result of an unintended software system command. In Outlook Express, for instance, you’ll find the system command Hang up when done. If the box in front of this phrase is checked, the connection will automatically be cut off every time you send or download electronic mail. Sometimes a misdirected click of your computer mouse will cause you to place a check in the box even though you do not realize it. Simply click on the check mark to make it disappear, and the hang-ups will discontinue.

These common e-mail troubles are rather easy to ascertain and when corrected will make your e-mailing experience more gratifying.

After doing the booth thing – okay I confess we actually enjoy this part and particularly when customers stop by to say hello- we went to see Karl Fosburg, Director of Systems Integration (and of course EM7 customer) present in the Network Management, Automation & Control track.

Looking quite snazzy and successful (which I could show you if only “someone” had remembered to bring the Flip video camera), Karl spun the story of how EM7 at Hughes came to be from the problems they were trying to solve to the vendor selection process to the benefits of the final solution. And yet, this really is not just a plug for us. The challenges/problems are ones that many IT operations guys and gals share not enough people or resources, too many alarms, not enough of the right alarms and then once you find the right solution, how to sell it to management.

I will share some advice from a smart user who’s had to deal with a lot of different kind of network management problems and all those vendors trying to help him with those problems.

Some advice from Karl for network managers looking for a new solution:

Get executive buy-in by clearly identifying the deficiencies in your current network management systems. What really helped Karl was to quantify the SLA credits that could be reduced and the savings to the business

Look at reducing the number of tools you have this has quantifiable benefits from reducing the costs of training, resources and recurring license fees to better integration.

Support from additional functional areas can also help the accounting department at Hughes was actually starting development of their own asset tracking system which expense and effort they avoided because this is already included in EM7.

Always perform an on-site proof of concept to verify that the vendors product works in YOUR environment the vendors worth their’ salt will do this for you.

And some general network management advice:

Have a well documented, structured naming convention for devices critical as your business grows and grows fast.

No management system will help if it doesn’t know about your systems – so spend the effort up front to nail down discovery processes.

Too many alarms has the same consequences as too few. Create a check and balances system to verify that systems are actually being monitored Hughes makes sure monitored systems show up in their IP/DNS database, in EMC/SMARTS (their manager of managers), in EM7 of course in and various other element managers.

Create a cross-functional “alarms” quality team that reviews network management implementation this is a very interesting idea – a team over at Hughes that meets once a week and agrees on their network management “cookbook” for what alarms are important to the business, an iterative process it turns out.

Last but not least, provide regular updates and accomplishments to executive management