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  • What light attenuation function does UDK use?

    - by ananamas
    I'm a big fan of the light attenuation in UDK. Traditionally I've always used the constant-linear-quadratic falloff function to control how "soft" the falloff is, which gives three values to play with. In UDK you can get similar results, but you only need to tweak one value: FalloffExponent. I'm interested in what the actual mathematical function here is. The UDK lighting reference describes it as follows: FalloffExponent: This allows you to modify the falloff of a light. The default falloff is 2. The smaller the number, the sharper the falloff and the more the brightness is maintained until the radius is reached. Does anyone know what it's doing behind the scenes?

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  • Business Logic Layer in MVC Application

    - by Subin Jacob
    In my ASP MVC application I decided to add another Business Layer and made the model only to have properties. All other functionality like save to db, get from db is done on this new Business layer. So now the controller will be calling this business layer and model for various operations. Is it a good approach to design like this? I decided not to use model for this purpose because I would need a number of models for different actions. (for eg, one for edit and other for create)

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  • VB.Net Sub reports problem in SS Reporting Services

    - by user65697
    I am trying to transfer over some MS Access reports to VB.Net via sql reporting services. Currently using VB.Net in Visual Studio 2008. I have 5 sub reports that need to run. Depending on the user selection any number of them can show at one time in the report viewer. So I assume I need to use a main report which holds the sub reports. How do I populate the data for each sub report when the main container report loads? Do I need to set the datasource of each subreport dynamically? Do I also need to dynamically load the subreports into the report viewer? Any code appreciated. Thanks

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  • Adding a ppa repo and get key signed - no valid OpenPGP data - proxy issue?

    - by groovehunter
    I want to get a ppa key signed I tried apt-key adv --keyserver keyserver.ubuntu.com --recv-keys A258828C Executing: gpg --ignore-time-conflict --no-options --no-default-keyring --secret-keyring /etc/apt/secring.gpg --trustdb-name /etc/apt/trustdb.gpg --keyring /etc/apt/trusted.gpg --primary-keyring /etc/apt/trusted.gpg --keyserver keyserver.ubuntu.com --recv-keys A258828C gpg: requesting key A258828C from hkp server keyserver.ubuntu.com gpgkeys: HTTP fetch error 7: couldn't connect to host gpg: no valid OpenPGP data found. gpg: Total number processed: 0 and wget -q http://ppa.launchpad.net/panda3d/ppa/ubuntu/dists/lucid/Release.gpg -O- | apt-key add - gpg: no valid OpenPGP data found I am behind a proxy , in apt.conf it is configured correctly Acquire::http::Proxy "http://proxy.mycompany.de:3128"; I also tried setting proxy export http_proxy="proxy.mycompany.de:3128" export https_proxy="proxy.mycompany.de:3128"

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  • Loading files during run time

    - by NDraskovic
    I made a content pipeline extension (using this tutorial) in XNA 4.0 game. I altered some aspects, so it serves my need better, but the basic idea still applies. Now I want to go a step further and enable my game to be changed during run time. The file I am loading trough my content pipeline extension is very simple, it only contains decimal numbers, so I want to enable the user to change that file at will and reload it while the game is running (without recompiling as I had to do so far). This file is a very simplified version of level editor, meaning that it contains rows like: 1 1,5 1,78 -3,6 Here, the first number determines the object that will be drawn to the scene, and the other 3 numbers are coordinates where that object will be placed. So, how can I change the file that contains these numbers so that the game loads it and redraws the scene accordingly? Thanks

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  • GPT Not mounting using "normal" GPT mounting techniques 12.04

    - by Roy Markham
    I've got two 2TB drivess: one MBR and the other GPT. sudo blckid /dev/sdb1 returns a blank. gdisk shows: Partition table scan: MBR: protective BSD: not present APM: not present GPT: present Found valid GPT with protective MBR; using GPT. Warning! Secondary partition table overlaps the last partition by 1970 blocks! You will need to delete this partition or resize it in another utility. Disk /dev/sdb: 3907027055 sectors, 1.8 TiB Logical sector size: 512 bytes Disk identifier (GUID): 38A1113D-B5E9-4B69-ABFF-ACB27AFB3DDD Partition table holds up to 128 entries First usable sector is 34, last usable sector is 3907027021 Partitions will be aligned on 8-sector boundaries Total free space is 2014 sectors (1007.0 KiB) Number Start (sector) End (sector) Size Code Name 1 34 262177 128.0 MiB 0C01 Microsoft reserved part 2 264192 3907028991 1.8 TiB 0700 Basic data partition mounting via fstab or -t gives same error when using NTFS or NTFS-3g "NTFS signature is missing" GParted says one partition is overwriting another, yet windows shows no errors at all. The drive is also mounted easily via MacOs (triple boot)

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  • Design Pattern for Complex Data Modeling

    - by Aaron Hayman
    I'm developing a program that has a SQL database as a backing store. As a very broad description, the program itself allows a user to generate records in any number of user-defined tables and make connections between them. As for specs: Any record generated must be able to be connected to any other record in any other user table (excluding itself...the record, not the table). These "connections" are directional, and the list of connections a record has is user ordered. Moreover, a record must "know" of connections made from it to others as well as connections made to it from others. The connections are kind of the point of this program, so there is a strong possibility that the number of connections made is very high, especially if the user is using the software as intended. A record's field can also include aggregate information from it's connections (like obtaining average, sum, etc) that must be updated on change from another record it's connected to. To conserve memory, only relevant information must be loaded at any one time (can't load the entire database in memory at load and go from there). I cannot assume the backing store is local. Right now it is, but eventually this program will include syncing to a remote db. Neither the user tables, connections or records are known at design time as they are user generated. I've spent a lot of time trying to figure out how to design the backing store and the object model to best fit these specs. In my first design attempt on this, I had one object managing all a table's records and connections. I attempted this first because it kept the memory footprint smaller (records and connections were simple dicts), but maintaining aggregate and link information between tables became....onerous (ie...a huge spaghettified mess). Tracing dependencies using this method almost became impossible. Instead, I've settled on a distributed graph model where each record and connection is 'aware' of what's around it by managing it own data and connections to other records. Doing this increases my memory footprint but also let me create a faulting system so connections/records aren't loaded into memory until they're needed. It's also much easier to code: trace dependencies, eliminate cycling recursive updates, etc. My biggest problem is storing/loading the connections. I'm not happy with any of my current solutions/ideas so I wanted to ask and see if anybody else has any ideas of how this should be structured. Connections are fairly simple. They contain: fromRecordID, fromTableID, fromRecordOrder, toRecordID, toTableID, toRecordOrder. Here's what I've come up with so far: Store all the connections in one big table. If I do this, either I load all connections at once (one big db call) or make a call every time a user table is loaded. The big issue here: the size of the connections table has the potential to be huge, and I'm afraid it would slow things down. Store in separate tables all the outgoing connections for each user table. This is probably the worst idea I've had. Now my connections are 'spread out' over multiple tables (one for each user table), which means I have to make a separate DB called to each table (or make a huge join) just to find all the incoming connections for a particular user table. I've avoided making "one big ass table", but I'm not sure the cost is worth it. Store in separate tables all outgoing AND incoming connections for each user table (using a flag to distinguish between incoming vs outgoing). This is the idea I'm leaning towards, but it will essentially double the total DB storage for all the connections (as each connection will be stored in two tables). It also means I have to make sure connection information is kept in sync in both places. This is obviously not ideal but it does mean that when I load a user table, I only need to load one 'connection' table and have all the information I need. This also presents a separate problem, that of connection object creation. Since each user table has a list of all connections, there are two opportunities for a connection object to be made. However, connections objects (designed to facilitate communication between records) should only be created once. This means I'll have to devise a common caching/factory object to make sure only one connection object is made per connection. Does anybody have any ideas of a better way to do this? Once I've committed to a particular design pattern I'm pretty much stuck with it, so I want to make sure I've come up with the best one possible.

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  • Best way to store a large amount of game objects and update the ones onscreen

    - by user3002473
    Good afternoon guys! I'm a young beginner game developer working on my first large scale game project and I've run into a situation where I'm not quite sure what the best solution may be (if there is a lone solution). The question may be vague (if anyone can think of a better title after having read the question, please edit it) or broad but I'm not quite sure what to do and I thought it would help just to discuss the problem with people more educated in the field. Before we get started, here are some of the questions I've looked at for help in the past: Best way to keep track of game objects Elegant way to simulate large amounts of entities within a game world What is the most efficient container to store dynamic game objects in? I've also read articles about different data structures commonly used in games to store game objects such as this one about slot maps, but none of them are really what I'm looking for. Also, if it helps at all I'm using Python 3 to design the game. It has to be Python 3, if I could I would use C++ or Unityscript or something else, but I'm restricted to having to use Python 3. My game will be a form of side scroller shooter game. In said game the player will traverse large rooms with large amounts of enemies and other game objects to update (think some of the larger areas in Cave Story or Iji). The player obviously can't see the entire room all at once, so there is a viewport that follows the player around and renders only a selection of the room and the game objects that it contains. This is not a foreign concept. The part that's getting me confused has to do with how certain game objects are updated. Some of them are to be updated constantly, regardless of whether or not they can be seen. Other objects however are only to be updated when they are onscreen (for example, an enemy would only be updated to react to the player when it is onscreen or when it is in a certain range of the screen). Another problem is that game objects have to be easily referable by other game objects; something that happens in the player's update() method may affect another object in the world. Collision detection in games is always a serious problem. I need a way of containing the game objects such that it minimizes the number of cases when testing for collisions against one another. The final problem is that of creating and destroying game objects. I think this problem is pretty self explanatory. To store the game objects then I've considered a number of different methods. The original method I had was to simply store all the objects in a hash table by an id. This method was simple, and decently fast as it allows all the objects to be looked up in O(1) complexity, and also allows them to be deleted fairly easily. Hash collisions would not be a major problem; I wasn't originally planning on using computer generated ids to store the game objects I was going to rely on them all using ids given to them by the game designer (such names would be strings like 'Player' or 'EnemyWeapon4'), and even if I did use computer generated ids, if I used a decent hashing algorithm then the chances of collisions would be around 1 in 4 billion. The problem with using a hash table however is that it is inefficient in checking to see what objects are in range of the viewport. Considering the fact that certain game objects move (as well as the viewport itself), the only solution I could think of in order to only update objects that are in the viewport would be to iterate through every object in the hash table and check if it is in the viewport or not, updating only the ones that are in the valid area. This would be incredibly slow in scenarios where the amount of game objects exceeds 500, or even 200. The second solution was to store everything in a 2-d list. The world is partitioned up into cells (a tilemap essentially), where each cell or tile is the same size and is square. Each cell would contain a list of the game objects that are currently occupying it (each game object would be inserted into a cell depending on the center of the object's collision mask). A 2-d list would allow me to take the top-left and bottom-right corners of the viewport and easily grab a rectangular area of the grid containing only the cells containing entities that are in valid range to be updated. This method also solves the problem of collision detection; when I take an entity I can find the cell that it is currently in, then check only against entities in it's cell and the 8 cells around it. One problem with this system however is that it prohibits easy lookup of game objects. One solution I had would be to simultaneously keep a hash table that would contain all the positions of the objects in the 2-d list indexed by the id of said object. The major problem with a 2-d list is that it would need to be rebuilt every single game frame (along with the hash table of object positions), which may be a serious detriment to game speed. Both systems have ups and downs and seem to solve some of each other's problems, however using them both together doesn't seem like the best solution either. If anyone has any thoughts, ideas, suggestions, comments, opinions or solutions on new data structures or better implementations of the existing data structures I have in mind, please post, any and all criticism and help is welcome. Thanks in advance! EDIT: Please don't close the question because it has a bad title, I'm just bad with names!

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  • Buy vs. Build - FTP Service

    - by Joel Martinez
    We have a need to FTP files that are generated by our system, so we're trying to decide whether we should spend the time to build something that meets our criteria (relatively easy, .NET has FTP functionality built in, among other more advanced libs from 3rd parties). Or if we should buy something off the shelf. Our requirements are roughly: Must be able to trigger a file send programmatically Needs to retry N number of times (configurable) Queryable status of FTP requests Callback on completion or fail of an FTP request I don't need to be sold on the relative simplicity of building something like that for myself. However I do want to do the due diligence of seeing what products are available ... because if something does exist that matches the requirements above, I wouldn't mind paying for it :-) Any thoughts or links would be greatly appreciated. Thanks!

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  • Routing PHP memcached calls to Oracle Coherence

    - by cj
    A new post Getting Started with the Coherence Memcached Adaptor from David Felcey shows how PHP memcached calls can automatically be routed to store data in Oracle Coherence 12c. This is possible now Coherence 12.1.3 supports Memcached clients using the Binary Memcached protocol. David's post shows how the Coherence Memcached adaptor can be configured as a proxy service that runs in the Coherence cluster. There's nothing particular to configure in the PHP application, except to enable memcached.use_sasl = 1 So what is Coherence? It is an "in-memory data grid solution", with a number of advanced features. You can read more in the Oracle Coherence 12C Data Sheet.

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  • How to install an older version of Java

    - by Alex Spurling
    I updated my installation of the sun-java6-jdk package today to version 6.24-1build0.10.10.1 after being prompted by the update manager. However this now causes some compilation failures so I'd like to revert back to the previous version that I had installed. I've tried using Synaptic but the 'Force Version' menu command is disabled. I've tried the following command to install the previous version sudo apt-get install sun-java6-jdk=6.22-0ubuntu1~10.10 But I'm not sure that I have the correct version: Reading package lists... Done Building dependency tree Reading state information... Done E: Version ‘6.22-0ubuntu1~10.10’ for ‘sun-java6-jdk’ was not found I've taken this version number from this changelog: https://launchpad.net/ubuntu/+source/sun-java6/+changelog Is this the correct way to install a previous version of a package? Have I got the correct version from the sun-java6 change log?

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  • Replace Broadcom "wl" driver with "b43"

    - by Laszlo Boros
    I'm using Ubuntu 10.04.4 LTS, and in my laptop there is a Broadcom BCM4312 wlan card. lspci output: 04:00.0 Network controller: Broadcom Corporation BCM4312 802.11b/g (rev 01) Subsystem: Broadcom Corporation Device 04b5 Flags: bus master, fast devsel, latency 0, IRQ 18 Memory at f4500000 (64-bit, non-prefetchable) [size=16K] Capabilities: [40] Power Management version 3 Capabilities: [58] Vendor Specific Information Capabilities: [e8] Message Signalled Interrupts: Mask- 64bit+ Queue=0/0 Enable- Capabilities: [d0] Express Endpoint, MSI 00 Capabilities: [100] Advanced Error Reporting Capabilities: [13c] Virtual Channel Capabilities: [160] Device Serial Number 81-ac-1d-ff-ff-12-54-92 Capabilities: [16c] Power Budgeting Kernel driver in use: wl Kernel modules: wl, ssb So as you can see, the current (and default) driver is wl - installed with jockey. But I have another Ubuntu based distribution on my laptop (BackTrack linux), which is also 10.04, but it has the b43 driver installed and the overall performance is MUCH better. So I would like to install it on this OS too, but even google didn't help me. So my question is how to install the latest b43 driver on my Ubuntu?

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  • Prevent Apache restarting automatically after upgrading packages

    - by HorusKol
    Following on from an earlier question: Is there a way to download security updates and notify admin without installing the update? A large number of packages interact with Apache (especially PHP) such that security updates to those packages can cause the server to attempt to restart the service. While my earlier question was answered, I'm now thinking that I need a different solution. So - is there are way to allow security updates to be applied using apt, have an email sent to an administrator, and, most importantly, prevent services from being restarted at the end of the installation/update process? The administrator will then be able to log in and restart the service manually.

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  • How to insert countdown into a video file

    - by student
    Is there an easy way to insert a big countdown clock after a given time position of a video file in linux? The countdown clock should count down in seconds from n to 0. Edit: I don't want to insert manually pictures showing the nth second. It is clear to me how to do that. What I want is an automatic way to do this: Set the number of seconds for the countdown (e.g. 64 or 80 seconds) Set the time where to insert the countdown in a given video And finally get the video with inserted countdown at specified position as a result. It would be nice if this would be possible in a graphical video editor like openshot. However it would also be ok to have a command line solution for this.

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  • StorageTek SL8500 Release 8.3 available

    - by uwes
    Boosting Performance and Enhancing Reliability with StorageTek SL8500 Release 8.3! We’re pleased to announce the availability of SL8500 8.3 firmware, which supports partitioning for library complexes, library media validation, drive tray serial number reporting, and StorageTek T10000D tape drives! StorageTek SL8500 8.3 support the following: Library Complex Partitioning: Provides support for partitioning across an SL8500 library complex  Supports up to 16 partitions per library complex   Library Media Validation: Utilizing StorageTek Library Console, users can initiate media verifications with our StorageTek T10000C/D tape drives on StorageTek T10000 T1 and T2 media  Supports 3 scan options: basic verify, standard verify and complete verify Please read the Sales Bulletin (Firmware reales 8.31) on Oracle HW TRC for more details. (If you are not registered on Oracle HW TRC, click here ... and follow the instructions..) For More Information Go To: Oracle.com Tape Page Oracle Technology Network Tape Page

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  • More Quick Interview Tips

    - by Ajarn Mark Caldwell
    In the last couple of years I have conducted a lot of interviews for application and database developers for my company, and I can tell you that the little things can mean a lot.  Here are a few quick tips to help you make a good first impression. A year ago I gave you my #1 interview tip: Do some basic research!  And a year later, I am still stunned by how few technical people do the most basic of research.  I can only guess that it is because it is so engrained in our psyche that technical competence is everything (see How to Manage Technical Employees for more on this idea) that we forget or ignore the importance of soft skills and the art of the interview.  Or maybe it is because we have heard the stories of the uber-geek who has zero personal skills but still makes a fortune working for Microsoft.  Well, here’s another quick tip:  You’re probably not as good as he is; and a large number of companies actually run small to medium sized teams and can’t really afford to have the social outcast in the group.  In a small team, everyone has to get along well, and that’s an important part of what I’m evaluating during the interview process. My #2 tip is to act alive!  I typically conduct screening interviews by phone before I bring someone in for an in-person.  I don’t care how laid-back you are or if you have a “quiet personality”, when we are talking, ACT like you are happy I called and you are interested in getting the job.  If you sound like you are bored-to-death and that you would be perfectly happy to never work again, I am perfectly happy to help you attain that goal, and I’ll move on to the next candidate. And closely related to #2, perhaps we’ll call it #2.1 is this tip:  When I call you on the phone for the interview, don’t answer your phone by just saying, “Hello”.  You know that the odds are about 999-to-1 that it is me calling for the interview because we have specifically arranged this time slot for the call.  And you can see on the caller ID that it is not one of your buddies calling, so identify yourself.  Don’t make me question whether I dialed the right number.  Answer your phone with a, “Hello, this is ___<your full name preferred, but at least your first name>___.”.  And when I say, “Hi, <your name>, this is Mark from <my company>” it would be really nice to hear you say, “Hi, Mark, I have been expecting your call.”  This sets the perfect tone for our conversation.  I know I have the right person; you are professional enough and interested enough in the job or contract to remember your appointments; and now we can move on to a little intro segment and get on with the reason for our call. As crazy as it sounds, I’ve actually had phone interviews that went like this: <Ring…> You:  “Hello?” Me:  “Hi, this is Mark from _______” You:  “Yeah?” Me:  “Is this <your name>?” You:  “Yeah.” Me:  “I had this time in my calendar for us to talk…were you expecting my call?” You:  “Oh, yeah, sure…” I used to be nice and would try to go ahead with the interview even after this bad start, thinking I was giving the candidate the benefit of the doubt…a second chance…but more often than not it was a struggle and 10 minutes into what was supposed to be a 45-minute call, I’m looking for a way to hang up without being rude myself.  It never worked out.  I never brought that person in for an in-person interview, much less offered them the job or contract.  Who knows, maybe they were some sort of wunderkind that we missed out on.  What I know is that they would never fit in with the rest of the team, and around here that is absolutely critical. So, in conclusion… Act alive!  Identify yourself!  And do at least the very basic of research.

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  • Is it possible to add registry entries to the wine registry and make illustrator work?

    - by Prasad
    I haven't done this kind of work before but I really need Adobe Illustrator to get work on ubuntu! I don't care if it is cs3 or 4. I have installed CS3 and 4 master collection on windows and with wine on ubuntu can't run it (yes, no registry entries added to the wine!) I can copy all the needed file to the /home/prasad/.wine/dosdevices/C: directory with hidden files included, but how to add registry entries to them? (windows registry editor like thing to wine) is it possible to make illustrator run in ubuntu like that, i tried to install Master collection but it failed number of times. I use ubuntu 10.10

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  • How to measure the right time to bring a new client?

    - by Byron Sommardahl
    My growing company has a team of developers working on a number of separate projects. Our developers depend on us to keep them working, and we depend on them to make our clients happy. Our projects have differing start and end dates, as you can imagine. The company's responsibility to the developers is to make sure we have clients waiting in the wings so that when one project ends, another can start. For now, finding clients is not a problem and not the topic of this question. What I'm trying to think through right now is, how can I best measure/view/evaluate the end dates of projects so that I know when I need to start courting the next client. Is there a tool that does this? If it's just a spreadsheet, what might it look like?

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  • How To Log Into Multiple Accounts On the Same Website At Once

    - by Chris Hoffman
    If you ever want to sign into two different accounts on the same website at once – say, to have multiple Gmail inboxes open next to each other – you can’t just open a new tab or browser window. Websites store your login state in browser-specific cookies. There are a number of ways you can get another browser window with its own cookies and stay logged into multiple accounts at once. HTG Explains: What is the Windows Page File and Should You Disable It? How To Get a Better Wireless Signal and Reduce Wireless Network Interference How To Troubleshoot Internet Connection Problems

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  • Computer Networks UNISA - Chap 14 &ndash; Insuring Integrity &amp; Availability

    - by MarkPearl
    After reading this section you should be able to Identify the characteristics of a network that keep data safe from loss or damage Protect an enterprise-wide network from viruses Explain network and system level fault tolerance techniques Discuss issues related to network backup and recovery strategies Describe the components of a useful disaster recovery plan and the options for disaster contingencies What are integrity and availability? Integrity – the soundness of a networks programs, data, services, devices, and connections Availability – How consistently and reliably a file or system can be accessed by authorized personnel A number of phenomena can compromise both integrity and availability including… security breaches natural disasters malicious intruders power flaws human error users etc Although you cannot predict every type of vulnerability, you can take measures to guard against the most damaging events. The following are some guidelines… Allow only network administrators to create or modify NOS and application system users. Monitor the network for unauthorized access or changes Record authorized system changes in a change management system’ Install redundant components Perform regular health checks on the network Check system performance, error logs, and the system log book regularly Keep backups Implement and enforce security and disaster recovery policies These are just some of the basics… Malware Malware refers to any program or piece of code designed to intrude upon or harm a system or its resources. Types of Malware… Boot sector viruses Macro viruses File infector viruses Worms Trojan Horse Network Viruses Bots Malware characteristics Some common characteristics of Malware include… Encryption Stealth Polymorphism Time dependence Malware Protection There are various tools available to protect you from malware called anti-malware software. These monitor your system for indications that a program is performing potential malware operations. A number of techniques are used to detect malware including… Signature Scanning Integrity Checking Monitoring unexpected file changes or virus like behaviours It is important to decide where anti-malware tools will be installed and find a balance between performance and protection. There are several general purpose malware policies that can be implemented to protect your network including… Every compute in an organization should be equipped with malware detection and cleaning software that regularly runs Users should not be allowed to alter or disable the anti-malware software Users should know what to do in case the anti-malware program detects a malware virus Users should be prohibited from installing any unauthorized software on their systems System wide alerts should be issued to network users notifying them if a serious malware virus has been detected. Fault Tolerance Besides guarding against malware, another key factor in maintaining the availability and integrity of data is fault tolerance. Fault tolerance is the ability for a system to continue performing despite an unexpected hardware or software malfunction. Fault tolerance can be realized in varying degrees, the optimal level of fault tolerance for a system depends on how critical its services and files are to productivity. Generally the more fault tolerant the system, the more expensive it is. The following describe some of the areas that need to be considered for fault tolerance. Environment (Temperature and humidity) Power Topology and Connectivity Servers Storage Power Typical power flaws include Surges – a brief increase in voltage due to lightening strikes, solar flares or some idiot at City Power Noise – Fluctuation in voltage levels caused by other devices on the network or electromagnetic interference Brownout – A sag in voltage for just a moment Blackout – A complete power loss The are various alternate power sources to consider including UPS’s and Generators. UPS’s are found in two categories… Standby UPS – provides continuous power when mains goes down (brief period of switching over) Online UPS – is online all the time and the device receives power from the UPS all the time (the UPS is charged continuously) Servers There are various techniques for fault tolerance with servers. Server mirroring is an option where one device or component duplicates the activities of another. It is generally an expensive process. Clustering is a fault tolerance technique that links multiple servers together to appear as a single server. They share processing and storage responsibilities and if one unit in the cluster goes down, another unit can be brought in to replace it. Storage There are various techniques available including the following… RAID Arrays NAS (Storage (Network Attached Storage) SANs (Storage Area Networks) Data Backup A backup is a copy of data or program files created for archiving or safekeeping. Many different options for backups exist with various media including… These vary in cost and speed. Optical Media Tape Backup External Disk Drives Network Backups Backup Strategy After selecting the appropriate tool for performing your servers backup, devise a backup strategy to guide you through performing reliable backups that provide maximum data protection. Questions that should be answered include… What data must be backed up At what time of day or night will the backups occur How will you verify the accuracy of the backups Where and for how long will backup media be stored Who will take responsibility for ensuring that backups occurred How long will you save backups Where will backup and recovery documentation be stored Different backup methods provide varying levels of certainty and corresponding labour cost. There are also different ways to determine which files should be backed up including… Full backup – all data on all servers is copied to storage media Incremental backup – Only data that has changed since the last full or incremental backup is copied to a storage medium Differential backup – Only data that has changed since the last backup is coped to a storage medium Disaster Recovery Disaster recovery is the process of restoring your critical functionality and data after an enterprise wide outage has occurred. A disaster recovery plan is for extreme scenarios (i.e. fire, line fault, etc). A cold site is a place were the computers, devices, and connectivity necessary to rebuild a network exist but they are not appropriately configured. A warm site is a place where the computers, devices, and connectivity necessary to rebuild a network exists with some appropriately configured devices. A hot site is a place where the computers, devices, and connectivity necessary to rebuild a network exists and all are appropriately configured.

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  • Microsoft StyleCop is now Open Source

    - by Scott Dorman
    I have previously talked about Microsoft StyleCop. For those that might not know about it, StyleCop is a source analysis tool (different from the static analysis that FxCop performs) that analyzes the source code directly. As a result, it focuses on more design (or style) issues such as layout, readability and documentation. In an interesting move (and one that I am happy to see), Microsoft has decided to make StyleCop an open source project (under the MS-PL license) available on CodePlex. (The project site isn’t up  yet, but should be in the next few weeks.) This will give the development community the opportunity to help contribute to the project, expanding support to other languages (currently it only supports C#), adding features, and fixing bugs. Shortly after the CodePlex site is up, StyleCop 4.4 will be released which includes support for C# 4.0 as well as a large number of bug fixes and other improvements. Technorati Tags: Code Style and Standard,StyleCop

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  • Save match details to SQLite or XML?

    - by trizz
    I'm making a (conceptual) system to simulate any kind of sports match (like soccer,basketball,etc) with actions (for example pass,pass,out,pass,score) so it will be like a real report. The main statistics (play time, number of actions etc.) I'm saving to a MySQL database, but the report itself, can contain more than 1000 actions per match. To avoid millions of records in my database I'm thinking of saving the detailled report in a SQLite database or a XML file. For every match played, a file will be created. When a user request the match details, I read the file for details. What is the best choice for this purpose? SQLite or XML?

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  • Cant Install TOR on Ubuntu Netbook 10.10 [closed]

    - by Prateek Mishra
    Possible Duplicate: How to install tor? I downloaded the tar.gz file from TORproject .org and unzipped it. I clicked everything inside the directories but nothing happened. I also tried to install the addon from here http://bit.ly/bSSNea . The addon is installed but I cant see the TOR button anywhere. I checked relevant the option in the preferences section of toolsaddons. How do I install it? EDIT - Executing: gpg --ignore-time-conflict --no-options --no-default-keyring --secret-keyring /etc/apt/secring.gpg --trustdb-name /etc/apt/trustdb.gpg --keyring /etc/apt/trusted.gpg --primary-keyring /etc/apt/trusted.gpg --keyserver keyserver.ubuntu.com --recv-keys 886DDD89 gpg: requesting key 886DDD89 from hkp server keyserver.ubuntu.com gpg: key 886DDD89: public key "deb.torproject.org archive signing key" imported gpg: no ultimately trusted keys found gpg: Total number processed: 1 gpg: imported: 1 (RSA: 1)

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  • Benchmarking CPU processing power

    - by Federico Zancan
    Provided that many tools for computers benchmarking are available already, I'd like to write my own, starting with processing power measurement. I'd like to write it in C under Linux, but other language alternatives are welcome. I thought starting from floating point operations per second, but it is just a hint. I also thought it'd be correct to keep track of CPU number of cores, RAM amount and the like, to more consistently associate results with CPU architecture. How would you proceed to the task of measuring CPU computing power? And on top of that: I would worry about a properly minimum workload induced by concurrently running services; is it correct to run benchmarking as a standalone (and possibly avulsed from the OS environment) process?

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  • Handbrake-powered VidCoder gets a native 64-bit version

    A while back, VidCoder -- the Windows video disc ripping program -- added support for Blu-ray discs. With Handbrake's engine under the hood, VidCoder offers an easy-to-use interface and simple batch processing of your video files. With the release of version 0.8, there's also now a native 64-bit version for those of you running Windows x64. A number of stability tweaks have also been introduced. As Baz pointed out in our comments last time, VidCoder is particular useful on netbooks. If you've got a 1024x600 screen, Handbrake may not even launch for you -- but VidCoder will fire up just fine. Take the new 64-bit version for a spin, and share your thoughts in the comments. Download VidCoderHandbrake-powered VidCoder gets a native 64-bit version originally appeared on Download Squad on Fri, 07 Jan 2011 17:00:00 EST. Please see our terms for use of feeds.Permalink | Email this | Comments

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