Linksys Media Hub NMH305

Storage is a crucial part of the digital lifestyle: We all need a place to put our stuff, and we need a way to access those files easily. Linksys has tried a few storage products in the past, but the Media Hub is its most ambitious effort. While it's not exactly a small business server that lets you set up user accounts – like the HP MediaSmart EX487 – and can't compete with the robust RAID and back-up options on Netgear ReadyNAS devices or those by Buffalo Technology, it has one glowing attribute: it's easy to use. Like most Apple products including the still viable Time Capsule, the Media Hub assumes you are not a certified Microsoft engineer or someone who carries USB key drives in your pocket 24x7. It's a smart product that eases you into the deeper features, with only a few caveats.

Setting up the Media Hub takes all of about three minutes. Connect one Ethernet cord to your router, turn it on, and you're done. Because the drive supports UPnP and works well with Windows, Apple iTunes, the Mac (thanks to Bonjour), and even Linux, you can expect to see the drive on your network without installing a driver or fussing with an IP address. Only when you do want to dive into the advanced features will you need the included setup CD or to access the drive's IP.

This NAS matches the styling of the new Linksys Multi-Room Home Audio gear – which is to say, it's gray and black and nothing too special compared to more elegantly designed network-attached storage devices. The difference between a media player you'd stick next to an HDTV, and this product, is that it will likely sit in a back closet somewhere. The Media Hub has two USB ports, one on the front and one on the back. There are very few buttons and lights. The NMH305 base model ships with one 500GB SATA drive and has one open bay. There's a power light and drive activity light – Linksys plans to release two additional models with higher capacities and an LCD screen that reports on drive status.

Performance on the Linksys Media Hub is just ho-hum – it's not going to set any speed records. About 6GB of MPEG-4 movie files took six minutes to transfer to the Media Hub, whereas the same transfer took 3 minutes to send to a home-built Windows Home Server and only 1 min 40 seconds to copy to the HP MediaSmart EX487 server. A 700MB collection of photos and documents took 50 seconds to write to the drive and 50 seconds to read, about 15 seconds longer than it took on the HP MediaSmart. The drive really showed some pokey behavior when we performed a full back-up of a desktop, which took about ten hours for about 200GB of data. The Media Hub has a gigabit Ethernet port, so it should be no slouch, but a real server adds some extra features to speed up disk copies.

source : reviews.digitaltrends.com

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Networking Topology

Think of a topology as a network's virtual shape or structure. This shape does not necessarily correspond to the actual physical layout of the devices on the network. For example, the computers on a home LAN may be arranged in a circle in a family room, but it would be highly unlikely to find a ring topology there.

Network topologies are categorized into the following basic types:

• bus
• ring
• star
• tree
• mesh

More complex networks can be built as hybrids of two or more of the above basic topologies.

Bus Topology

Bus networks (not to be confused with the system bus of a computer) use a common backbone to connect all devices. A single cable, the backbone functions as a shared communication medium that devices attach or tap into with an interface connector. A device wanting to communicate with another device on the network sends a broadcast message onto the wire that all other devices see, but only the intended recipient actually accepts and processes the message.

Ethernet bus topologies are relatively easy to install and don't require much cabling compared to the alternatives. 10Base-2 ("ThinNet") and 10Base-5 ("ThickNet") both were popular Ethernet cabling options many years ago for bus topologies. However, bus networks work best with a limited number of devices. If more than a few dozen computers are added to a network bus, performance problems will likely result. In addition, if the backbone cable fails, the entire network effectively becomes unusable.

Ring Topology

In a ring network, every device has exactly two neighbors for communication purposes. All messages travel through a ring in the same direction (either "clockwise" or "counterclockwise"). A failure in any cable or device breaks the loop and can take down the entire network.

To implement a ring network, one typically uses FDDI,SONET, or Token Ring technology. Ring topologies are found in some office buildings or school campuses.

Star Topology

Many home networks use the star topology. A star network features a central connection point called a "hub" that may be a hub, switch, and router. Devices typically connect to the hub with Unshielded Twisted Pair (UTP) Ethernet.

Compared to the bus topology, a star network generally requires more cable, but a failure in any star network cable will only take down one computer's network access and not the entire LAN. (If the hub fails, however, the entire network also fails.)

Tree Topology

Tree topologies integrate multiple star topologies together onto a bus. In its simplest form, only hub devices connect directly to the tree bus, and each hub functions as the "root" of a tree of devices. This bus/star hybrid approach supports future expandability of the network much better than a bus (limited in the number of devices due to the broadcast traffic it generates) or a star (limited by the number of hub connection points) alone.

Mesh Topology

Mesh topologies involve the concept of routes. Unlike each of the previous topologies, messages sent on a mesh network can take any of several possible paths from source to destination. (Recall that even in a ring, although two cable paths exist, messages can only travel in one direction.) Some WANs, most notably the Internet, employ mesh routing.

A mesh network in which every device connects to every other is called a full mesh. As shown in the illustration below, partial mesh networks also exist in which some devices connect only indirectly to others.

Summary

Topologies remain an important part of network design theory. You can probably build a home or small business computer network without understanding the difference between a bus design and a star design, but becoming familiar with the standard topologies gives you a better understanding of important networking concepts like hubs, broadcasts, and routes.

source : compnetworking.about.com

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Simple Steps To Basic Wireless Hacking

The intent of this article is to show you information on basic wireless hacking along with just how important it is to secure your wireless Network. Please use this information wisely. I am not responsible for what you and your friends do with this information.

Today it is very easy to set up a wireless network. Basically plug in the router a few clicks on your computer and away you go. The average person can go to his or her local electronic store and pick up a wireless router for as cheap as 40 bucks. The Problem comes in when securing the network. A large amount of people don't take the time to learn how to, or care to set up security.. How much damage can some one do if they connect to a wireless network?

Well in this article I will show you just how easy it is to connect to one of these unsecured networks and what kind trouble can be caused. I am going to use just some built in tools of Windows.

How Simple is it to find a Unsecured Network?

In this example I am just using the windows wireless management tool. This will work fine if you are not on the move. If you are scanning for networks in a car or on your bike I would strongly recommend NetStumbler .

As you can see here just by looking at what networks are available close to my home, There is at least one unsecured network. I would be willing to bet you could go around your block and find at least one open network. I am going to use this Linksys network in my example.

So just how simple is it to connect to an Unsecurred network?
I just double clicked on the open linksys network.
It will warn you that you are connecting to a unsecure network.

Click Connect Anyways

Now I can start Browsing the Internet

What can some one do if they connect to unsecured network?

In this example this wireless network is still set at the default settings including the Administrator password. A simple search on http://www.routerpasswords.com you can find just about any wireless router Default password. SInce this is a linksys router the default password would be admin. Since most wireless routers are the default gateway, I will do a quick command in dos to find out what the default gateway is.

Click on start > Run

Type CMD and click ok

In the Dos window type ipconfig then hit enter

I look for the information under my wireless network card. The default gateway is 192.168.1.1 Type this in your Browser to connect to the router.

You will be prompted for a username and password.

Leave the username blank or type root

Since this is a linksys router I will use the password admin

To find out the default password for just about any router check out

http://www.routerpasswords.com/

If they did not change there router password you should be able to get in to the configuration pages of the router.

I am now connected to the router. This gives me complete access to see who is on the network. I can also do things such as set up security, open ports, and so much more.

How do you see who is connected to the network?

- Click on Status

- Click on Local Network

- Click on DHCP Client Table button

You should now see all computers that have been assigned an IP address by the router. Not all the computers on the network may not be connected at that time but a simple ping will let you know.

You could run a port scanner on each of these computer's IP address to find open ports such as ssh, telnet, termainal service and so on.

SInce we are able to configure the router we could open up ports and let any one on the internet have access to this network. We could also have a little fun by setting up wireless security on the network and locking out the owner of his or her's own network.

Lets say you could not get in to configure the router there still is a lot of trouble that can be caused just by being connected on the network. You could set up a Network packet capturing program such as Ethereal. Then use it to Scan for information such as username and passwords from websites they may login to.

You could also go out and cause some trouble on the web and it would trace back to there IP address.

At the Least you could enjoy the free internet. You get lost some where, get connected real quick and take advantage of google maps. Could come in handy in a pinch.

I hope this article got you thinking a little bit and if your wireless network is not secure, I hope this has convinced you to take the time to set it up.

source : www.mixeduperic.com

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Router Commands

In this section you will learn about the router commands, configurations, privileged mode commands, routing protocols, cisco labs and network configurations.

There are hundreds of basic and advance level commands of a router. It is not easy to remember all the commands. But some commands are frequently used and can be remembered with some practice. I have provided a list of the most commonly used commands based on their features and usage. You will find here some basic terminology of a router.

Routing: Routing is a process of moving the data (packets) through an inter network. Routing performs the two basic tasks. Define the paths for a packet and then forward the packets on the basis of defined paths. Routing can also be defined as the communication between two or more logically and physical networks and this communication (packet transfer) is brought by a router.

First of all you should remember the keyboard shortcuts of a router.

Keyboard Shortcuts
CTRL-N - show next command
CTRL-P - show previous command
SHIFT-CTRL-6 – Break

Configuring the Router

You will be able to learn the basic commands for configuring a router.
sh running-config - details the running configuration file (RAM)
sh startup-config - displays the configuration stored in NVRAM
setup - Will start the the automatic setup; the same as when you first boot the router
config t - use to execute configuration commands from the terminal
config mem - executes configuration commands stored in NVRAM; copies startup-config to running-config

config net - used to retrieve configuration info from a TFTP server
copy running-config startup-config - copies saved config in running config (RAM) to NVRAM or "write memory" for IOS under ver.11
copy startup-config running-config - copies from non-volatile (NVRAM) to current running config (RAM)
boot system flash - tells router which IOS file in flash to boot from
boot system tftp - tells router which IOS file on the tftp server to boot from
boot system rom - tell router to boot from ROM at next boot
copy flash tftp - Copies flash to tftp server
copy tftp flash - Restores flash from tftp server
copy run tftp - Copies the current running-config to tftp server
copy tftp run - Restores the running-config from tftp server

General Commands

Here is a list of the general commands. These are the basic level commands and most commonly used
no shutdown - (enables the interface)
reload - restarts the router
sh ver - Cisco IOS version, uptime of router, how the router started, where system was loaded from, the interfaces the POST found, and the configuration register
sh clock - shows date and time on router
sh history - shows the history of your commands
sh debug - shows all debugging that is currently enabled
no debug all - turns off all debugging
sh users - shows users connected to router
sh protocols - shows which protocols are configured
banner motd # Your customized message here # - Set/change banner
hostname - use to configure the hostname of the router
clear counters - clear interface counters

Privileged Mode commands of a router

Learn how to work in the privileged mode of a router.
enable - get to privileged mode
disable - get to user mode
enable password - sets privileged mode password
enable secret - sets encrypted privileged mode password
Setting Passwords on router
Here you will be able to learn how to set the password on a router.
enable secret - set encrypted password for privileged access
enable password - set password for privileged access (used when there is no enable secret and when using older software)
Setting the password for console access:
(config)#line console 0
(config-line)#login
(config-line)#password
Set password for virtual terminal (telnet) access (password must be set to access router through telnet):
(config)#line vty 0 4
(config-line)#login
(config-line)#password
Set password for auxiliary (modem) access:
(config)#line aux 0
(config-line)#login
(config-line)#password

Router Processes & Statistics

By these command you can see the statistics and different processes of the router.
sh processes - shows active processes running on router
sh process cpu - shows cpu statistics
sh mem - shows memory statistics
sh flash - describes the flash memory and displays the size of files and the amount of free flash memory
sh buffers - displays statistics for router buffer pools; shows the size of the Small, Middle, Big, Very Big, Large and Huge Buffers
sh stacks - shows reason for last reboot, monitors the stack use of processes and interrupts routines

IP Commands

Here is a list of the IP Commands
Configure IP on an interface:
int serial 0
ip address 157.89.1.3 255.255.0.0
int eth 0
ip address 2008.1.1.4 255.255.255.0

Other IP Commands:

sh ip route - view ip routing table
ip route [administrative_distance] - configure a static IP route
ip route 0.0.0.0 0.0.0.0 - sets default gateway
ip classless - use with static routing to allow packets destined for unrecognized subnets to use the best possible route
sh arp - view arp cache; shows MAC address of connected routers
ip address 2.2.2.2 255.255.255.0 secondary - configure a 2nd ip address on an interface
sh ip protocol

CDP Commands (Cisco Discovery Protocol uses layer 2 multicast over a SNAP-capable link to send data):

sh cdp neighbor - shows directly connected neighbors
sh cdp int - shows which interfaces are running CDP
sh cdp int eth 0/0 - show CDP info for specific interface
sh cdp entry - shows CDP neighbor detail
cdp timer 120 - change how often CDP info is sent (default cdp timer is 60)
cp holdtime 240 - how long to wait before removing a CDP neighbor (default CDP holdtime is 180)
sh cdp run - shows if CDP turned on
no cdp run - turns off CDP for entire router (global config)
no cdp enable - turns off CDP on specific interface

IPX Commands

Enable IPX on router:
ipx routing
Configure IPX + IPX-RIP on an int:
int ser 0
ipx network 4A

Other Commands:

sh ipx route - shows IPX routing table
sh ipx int e0 - shows ipx address on int
sh ipx servers - shows SAP table
sh ipx traffic - view traffic statistics
debug ipx routing activity - debugs IPS RIP packets
debug ipx sap - debugs SAP packets

Routing Protocols

RIP, IGPR and OSPF are the routing protocols and here is a list of the commands for the working on the routing protocols.
Configure RIP:
router rip
network 157.89.0.0
network 208.1.1.0
Other RIP Commands:
debug ip rip - view RIP debugging info
Configure IGRP:
router IGRP 200
network 157.89.0.0
network 208.1.1.0
Other IGRP Commands:
debug ip igrp events - view IGRP debugging info
debug ip igrp transactions - view IGRP debugging info
Access Lists
Here is a list of the Access list command of a router.
sh ip int ser 0 - use to view which IP access lists are applies to which int
sh ipx int ser 0 - use to view which IPX access lists are applies to which int
sh appletalk int ser 0 - use to view which AppleTalk access lists are applies to which int
View access lists:
sh access-lists
sh ip access-lists
sh ipx access-lists
sh appletalk access-lists
Apply standard IP access list to int eth 0:
access-list 1 deny 200.1.1.0 0.0.0.255
access-list 1 permit any
int eth 0
ip access-group 1 in
Apply Extended IP access list to int eth 0:
access-list 100 deny tcp host 1.1.1.1 host 2.2.2.2 eq 23
access-list 100 deny tcp 3.3.3.0 0.0.0.255 any eq 80
int eth 0
ip access-group 100 out
Apply Standard IPX access list to int eth 0:
access-list 800 deny 7a 8000
access-list 800 permit -1
int eth 0
ipx access-group 800 out
Apply Standard IPX access list to int eth 0:
access-list 900 deny sap any 3378 -1
access-list 900 permit sap any all -1
int eth 0
ipx access-group 900 out

WAN Configurations Commands

Networking over WAN is the main functionality of a router. The most common use of a router is for the WAN connectivity. Here is a list of the commands for the different methods of the WAN connectivity.

PPP Configuration

Point to point protocol is a method for the WAN connectivity and you will find here some commands of PPP.
encapsulation pppppp authentication
ppp chap hostname
ppp pap sent-username
sh int ser 0 - use to view encapsulation on the interface

Frame-Relay Configuration

One of the methods for the WAN connectivity is the Frame Relay. Find here some basic commands for the WAN connectivity through Frame Relay.
encapsulation frame-relay ietf - use IETF when setting up a frame-relay network between a Ciscorouter and a non-Cisco router
frame-relay lmi-type ansi - LMI types are Cisco, ANSI, Q933A; Cisco is the default; LMI type is auto-sensed in IOS v11.2 and up
frame-relay map ip 3.3.3.3 100 broadcast - if inverse ARP won't work, map Other IP to Your DLCI # (local)
keep alive 10 - use to set keep alive
sh int ser 0 - use to show DLCI, LMI, and encapsulation info
sh frame-relay pvc - shows the configured DLCI's; shows PVC traffic stats
sh frame-relay map - shows route mapssh frame-relay lmi - shows LMI info

Miscellaneous Commands

In the last but not least here is a list of the some miscellaneous and useful commands
sh controller t1 - shows status of T1 lines
sh controller serial 1 - use to determine if DCE or DTE device
(config-if)#clock rate 6400 - set clock on DCE (bits per second)
(config-if)#bandwidth 64 - set bandwidth (kilobits)

source : www.networktutorials.info

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Windows 7 Security

By : Sonny Discini
Right now, Windows 7 looks very much like Windows Vista because enhancements to the appearance and feel aspects of the operating system typically come late in the development process. Lucky for us, much of the awaited security functionality has already made its way into the beta build and we're going to look at some of the new changes for Windows 7.

Old friends, new twists

Returning from Windows Vista are Kernel Patch Protection, Service Hardening, Data Execution Prevention, Address Space Layout Randomization, and Mandatory Integrity Levels

Windows XP SP2 gave us the Security Center. Windows 7 discards this and in its place is an Action Center that incorporates alerts from 10 existing Windows features: Security Center; Problem, Reports, and Solutions, Windows Defender; Windows Update; Diagnostics; Network Access Protection; Backup and Restore; Recovery; and User Account Control.

In Windows 7, users can adjust consent prompt behavior using a slider control, if they have administrative privileges. Microsoft says they'll still be protected against malicious software, even if they never see another alert. While this may or may not be true, users have been conditioned to see alerts whenever something is happening. Without them, perhaps a false sense of security will develop on the part of the end user.

Windows Filtering Platform

Windows 7 introduces something called the Windows Filtering Platform (WFP). The idea is that third parties can take advantage of aspects of the Microsoft Windows Firewall in their own products. Microsoft says "third-party products also can selectively turn parts of the Windows Firewall on or off, enabling you to choose which software firewall you want to use and have it coexist with Windows Firewall."

While this sounds nice on paper, I can't see a vendor teaming their product with the Windows firewall. Smart money says they'll just use their own and ignore the Microsoft solution.

One nice thing to note about Windows 7 is that it makes it easier to configure that all-important home network. When users hit network problems, they curse the firewall and they're often right to. Windows 7 addresses the problem by taking over home network setup and making sure the firewall doesn't interfere.

We also see that scrollbars were removed in the configuration settings screen, as has the Software Explorer feature, and real-time protection in Windows 7 has been improved to reduce the impact on overall system performance. A welcome change from the bloat of Vista.

An inclusive BitLocker

Vista sailed in along with a fleet of new security features, among them BitLocker, a whole-disk encryption tool designed to protect your data even after an attacker makes off with your laptop. BitLocker utilizes a chip called a Trusted Protection Module (TPM). The Vista TPM transparently decrypts the drive once you've authenticated yourself with a password or smart card. A laptop thief can't break into the locked drive, even after booting to a different OS or moving the drive to another computer.

BitLocker drive encryption also supports removable storage devices, such as flash memory drives and portable hard drives has been added in Windows 7. This means that users can keep sensitive data on all of their USB storage devices as well as the physical drives on the host mentioned above.

As a side note to Bitlocker, using groups, you can ban writing to any removable drive that isn't BitLocker-protected. It's a very useful tool against the very real problem known as podslurping. With this policy in place, employees can still bring in the virus-of-the-month on an unprotected drive, but they can't take away an unprotected copy of the personnel database. It's also helpful to know that BitLocker to Go also allows users to securely share data with other users who have not yet deployed Windows 7.

That said, the testing I performed proved otherwise. I could not get this to work so I went to Microsoft and they confirmed that this is an issue in the beta build but will be fixed before final GA release.

Biometrics, System Restore and AppLocker

Biometrics enhancements include easier reader configurations, allowing users to manage the fingerprint data stored on the computer and control how they log on to Windows 7. And System Restore includes a list of programs that will be removed or added, providing users with more useful information before they choose which restore point to use. Restore points are also available in backups, providing a larger list to choose from, over a longer period of time.

I've seen more problems caused by System Restore than solved by it; I'm not a big fan. Still, users often resort to it when trying to clean up a real or imagined malware problem. In Windows 7, you'll at least have a clear idea of what collateral damage may result, as it lists all programs and drivers that would be removed or brought back by invoking a particular System Restore point. It's way better than guessing at the right restore point and hoping for the best, which is what you have to do now.

Another enhancement is AppLocker, accessed through Local Security Policy. It's a way to control which programs users can and can't use, and it's a lot more flexible than Vista's Software Restriction Policies. Still, it's not for the average user. Most IT shops should be pleased with this enhancement. I can see it being tailored to just about any corporate need.

Virtually all the changes in the security area are simply tweaking and improving on existing Vista features. But then, that's what Windows 7 is all about, right? While the enhancements seen thus far in the beta are nice, they aren't stunning.

I hope to see even more improvements before Windows 7 hits the streets.

source : www.enterpriseitplanet.com

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