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Network Analysis





Network analysis is the process of identifying and remediating the processes and systems within a network, including performance, connectivity and security. The process is performed through the use of tools developed for monitoring and analyzing network activity. Network problems that involve finding an optimal way of doing something are studied under the name combinatorial optimization. Examples include network flow, shortest path problem, transport problem, transshipment problem, location problem, matching problem, assignment problem, packing problem, routing problem, Critical Path Analysis and PERT (Program Evaluation & Review Technique).

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Everyone has always said HUBs are bad and send information to ALL devices

I have an employee that needs another PC setup next to them ASAP and I do not have time to run another 100' CAT6 cable from the switch to this PC, therefore I just setup a small $10 cheap hub as follows

 1. patch cord from SWITCH to HUB
 2. patch cord from HUB to PC #1
 3. patch cord from HUB to PC #2

Which one of the below options will happens since a HUB is now in the mix when PC #2 updates a file on the Windows 2012 R2 file server since I did not wire back to the Cisco switch ?

    ** Option #1 = PC #2 sends info to ALL 100+ devices on my network, with only the file server accepting the data

    ** Option #2 = PC #2 sends info to ALL devices that are plugged into the hub (i.e. only PC #1 and the switch), with only the file server accepting the data

   ** Option #3 = something else ?
Free Tool: Port Scanner
LVL 11
Free Tool: Port Scanner

Check which ports are open to the outside world. Helps make sure that your firewall rules are working as intended.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Hi All

I have a couple of clients with SonicWALL TZ 300 routers, and am considering having them purchase SonicWALL’s Capture Advanced Threat Protection because it seems like a damn good idea! As I understand it, it's cloud based sandbox system.

Would appreciate hearing everyone's thoughts, concerns or experiences with the product or similar products.

Thank you!

Customer has a LAN with a few PCs and some tabs/phones that connect to Internet via their LAN (partly wireless). Internet access is through a 4G mobile modem (other options not available). This has worked well for nearly a year.

Lately they have experienced a lot more data traffic. Since they pay per GB to the mobile operator they try to find what is causing the increased data usage. I have checked the wireless LAN, but can't see anything wrong. Also changed the encryption key.

Question is - is there a way to easily monitor the traffic from the LAN to the 4G network. A packet sniffer might do the job, but results are quite difficult to analyze. Is there an easier way? Thinking of monitoring each LAN IP and traffic to/from the 4G router.
hi, I need to find when user loging to our web site, which address or which zip/postcode, is there is a way to do that?
Other than find broadband service provider location.
Any tools may be i can buy more help full.Thanks
Dear All

I installed Fortigate 60 E and its blocking all the videos and Audios. Also its blocking all the social media sites.
Hi Guys,

I had to switch our two WAN Interfaces on SonicWALL, (Thus X1 & X2)

1.  I switched the public IP configuration under Interface Settings
2.  and changed all the NAT policies, switching X1 & X2 for all rules

My questions,

a.  Is there any other rule(s) that need to be changed to switch primary internet access for LAN users between X1 & X2?

b.  I've noticed that some NAT rules refer to an "address object" rather than the interface (X1/X2) directly.  
These I did not change as the object's public address was still correct.  Is there a difference in referring to the interface (X1/X2) directly, or using an object instead?  
In my case, where I had to switch X1 & X2 ... the rules with objects made things a bit easier as it stayed the same.  Is this the only difference using an object or referencing to the interface directly?
My son's computer keeps having internet connection issues.

-Is playing on a minecract server / minecraft client

Sometimes these apps are also open

He is playing on a minecraft server.  and begins to experience lag more and more frequently before the crash.
Is there any way to track down the culprit?  We could assume that it is not enough RAM and go buy more RAM and the problem happens again and we are no better off.

I am looking for a way to gather information that can help tells us what thing( s ) is causing the problem(  s  )

sys info 2systxt.txt
How do I change a Public Network to Private. Windows 8.1 and 10.

There is no ability to Make this PC discoverable.

I downloaded and install the free SolarWinds Real-Time Bandwidth Monitor. I need help to configure it. Its asking for the Community String. What's the Community String? Where do I find it?
We already have SonicWall CGSS but that doesn't allow us to audit what websites a person or group of people are visiting. Any services / programs out there that will do that without going to Untangle or something cost prohibitive like that?
Get your Disaster Recovery as a Service basics
Get your Disaster Recovery as a Service basics

Disaster Recovery as a Service is one go-to solution that revolutionizes DR planning. Implementing DRaaS could be an efficient process, easily accessible to non-DR experts. Learn about monitoring, testing, executing failovers and failbacks to ensure a "healthy" DR environment.

We are using a Sonicwall TZ 205 firewall behind a Barracuda Link Balancer 330. I have two ISP connections coming into the Barracuda (Sprint and Comcast). I have 5 public IPs from each ISP. We currently have the following servers behind the firewall (Exchange 2013, Microsoft Remote Access for VPN and an ISeries database server) that are accessed using the Sprint public IPs.

Internet ---Sprint Router (65.xxx.xxx.17)

Internet ---Comcast Router (173.xxx.xxx.142)

Barracuda Link Balancer 330 (65.xxx.xxx.18 and 173.xxx.xxx.139)
Sonicwall TZ205 (65.xxx.xxx.20)

Internal Servers

In the Sonicwall, the Sprint public IPs are all NAT's to the internal private IPs.

 I would like to setup some inbound redundancy for these servers by mapping them to some of the Comcast public IPs. The Barracuda has only one connection to the Sonicwall so I don't know if I need to add another physical interface to the Sonicwall on interface X2 and configure it with the Comcast information and then put a switch between the Barracuda and Sonicwall. I know how to setup the DNS records to check if one line goes down, but I am unsure as to the physical connections.

Thank you.
I'm looking for utilities/methods to monitor my organization's Server 2016 network that will let me know (via email alerts) any time that these items go offline:

- Server 2016 AD domain controllers
- Wireless Access Points (WAPs)
- Network Attached Storage Device (NAS)
- SonicWALL firewall
- Primary internet service
- Fail over internet service

I am also interested in any monitoring solutions that will let me know if the Server 2016 hard drives are running low on space, etc.

What are some good website services or other software that will allow this to be done using methods such as pings or SNMP monitoring?
I am having trouble getting netflow to work on PRTG from Cisco 800, 1800 and 2800 series routers.  

I configure a router to export v5 or v9 flows - same problem on each.

I go into PRTG and set up a corresponding sensor.  

I want detail, so in the channels section I tick detail on a couple of categories.  set all the other bits like listening IPS and port number

The sensor will go to 'OK' with a green icon, but not receive any data.  I try their netflow test tool and can see data hitting the machine, so I know that netflow is set up and the firewall is not an issue.  Playing with settings yields no results.  

I then set up a netflow listener for another router, but I don't change the channel definitions and it works!

I realise I need more detail, so I go into the sensor settings and tick 'No' for a couple of channels and 'Detail' for the OTHER channel.  

The graphs disappear.  The sensor stays green, but it show no data.  I wait 1/2 an hour and still no luck

I set the channel definitions back to defaults and wait.  The sensor still does not show any data.  This would be consistent with the first router.  Channel definitions were changed from defaults and the sensor will never work.  

I delete the sensor and add a new one with the same settings as before.  No data shows.  A broken sensor persists even after deleting it.  

Is this a PRTG bug or am I doing something wrong?

I want detailed graphs so I can identify what data is hogging bandwidth, …
Hi All,

We currently have Business Voice Edge VIOP from Comcast which is their proprietary voice platform. They have provisioned and require a 50Mb circuit over their fiber backbone to our office to services SLA for their voice platform. Thus far, as far as reliability, I have to say that we have had no real issues with call quality over the past year of usage.

Management has decided to move offices earlier than expected, and we overlooked Comcasts terms and conditions regarding portability of service to locations that do not currently have a Comcast fiber backbone in their building – which the location we are moving to does not have Comcast fiber. They are also not willing to work with us to temporarily provision over another circuit. At this point, we have three options – ranked in order of preference, and I wanted to know if anyone has experience and any recommendations to help in making the right decision. Here are the scenarios:

1.)      Upgrade with Comcast to the new location and wait 6 months for them to build out their own fiber (includes city permits) to the new office.
a.      One of two options in this cast to get service to our new office:
i.      Implement RingCentral month-to-month as a temporary VOIP platform while we wait. Forwarding temporary numbers to main numbers.
ii.      Implement a Ethernet Dedicated E-Line (point to point) between our office via layer 2 routing.
2.)      Terminate with Comcast and incur termination charges – something that we don’t want to do.…
For some reason no one in the company can visit https://www.amctheatres.com/ we get the following error message.
The requested URL was rejected. Please consult with your administrator.

Your support ID is: 15532489170173462385

[Go Back]

It works fine outside of the network.
I have checked DNS for root kits and nothing came up. I changed the DNS on two computer to point to google ( same result.

I did trace route and it looks normal.

Tracing route to over a maximum of 30 hops

  1     2 ms     3 ms     2 ms  x
  2    <1 ms    <1 ms    <1 ms  x
  3     2 ms    16 ms     7 ms  r-uwmadison-isp-ge-7-0-1-2931.wiscnet.net []
  4     6 ms     6 ms     6 ms  r-222wwash-isp-ae2-3900.wiscnet.net []
  5    28 ms    22 ms    23 ms  madix-hurricane.net.wisc.edu []
  6    38 ms    19 ms    24 ms  10ge14-2.core1.chi1.he.net []
  7    24 ms    23 ms    23 ms  100ge14-1.core2.chi1.he.net []
  8    35 ms    29 ms    29 ms  100ge12-1.core1.mci3.he.net []
  9    30 ms    30 ms    34 ms  arsalon-technologies.gigabitethernet1-9.core1.mci3.he.net []
 10    31 ms    30 ms    30 ms  204-13-97-250.arsalon.net []
 11    40 ms    40 ms    40 ms

I did a packet capture and it looks normal.

so I am not sure what the issue is.

Any thoughts would be appreciated. Thanks!!!
I'm getting conflicting answers on this question:

What is the best NMAP command to use when you want to list all devices in the same network quickly after you successfully identified a server whose IP address is

Nmap -T4 -F

Nmap -T4 -q

Nmap -T4 -O

Nmap -T4 -r

Some sites say to use the -F option others say -O

Sites saying to use -F:
Example Question/Answer: https://www.passleader.com/downloadable/download/sample/sample_id/5692/
(explination of answer) https://svn.nmap.org/nmap/zenmap/share/zenmap/config/scan_profile.usp

Another -F answer: http://www.certifychat.com/threads/2017-mar-new-312-50v9-pdf-and-312-50v9-vce-free-version-share.2439/

Can anyone give me a definitive answer and explain why?
I want to record all unsuccessful login attempts in Kiwi Syslog, is it possible?
Has anyone used a free bandwidth monitor.  We can't afford the ones that are out there that cost.

Any help would be appreciated.
Hi, we are in work group environment, using cisco c3925 as the router facing Internet. How can we know the Internet pages where users access? Do you know any free tool or devices? Many thanks.
Nothing ever in the clear!
Nothing ever in the clear!

This technical paper will help you implement VMware’s VM encryption as well as implement Veeam encryption which together will achieve the nothing ever in the clear goal. If a bad guy steals VMs, backups or traffic they get nothing.

Hello ,

I have 2 questions about timestamp ;

1. I have try to convert time stamp value to normal time but it was returned anormal dates :) what is the format of this TS val ?
2. As far as i read on the http://www.networksorcery.com/enp/protocol/tcp/option008.htm 

This field is only valid if the ACK bit is set in the TCP header.

but nearly all SYN packets in normal traffic not a DDOS has TSval  while ack was not sScreen-Shot-2017-08-27-at-18.05.41.pnget

I have a couple of WAN connections and used by few users to access company services like : Mail,Web Applications...etc.
Both Lines have "A" Records with our ISP. if one line is down,  is it possible to redirect the users to access services through the back up line ? or can you suggest best scenario ?

Best Regards
My "server1" Windows 2012 R2 has two NICs, with two static IPs, and

When ping  "server1" from a client on the 192.168.20.x it replies with the IP and says it cannot find it

How can I get "server1" to reply as instead ?
I have encountered a security breach, the most likely explanation is packet sniffing of http data. The issue is that we have many companies each assigned to their own separate VLANs. Can packet sniffers sniff across different Vlans if they are connected to the same  the same switch or AP? I didn't think that was possible?
In the search tool - you can select source or destination address that EQUALS, NOT EQUALS, IS EITHER, IS NEITHER. But what I haven't figured out is how to search by subnet. e.g. show me all the traffic with Destination in the subnet. Is that possible?
Hello Experts, I need some assistance since I'm not that familiar with SonicWall

I have a TZ215 FW with both, LAN and WLAN active configurations, I upgraded my ISP BW from 10Mbps to 20Mbps (cable provider) and just realized that everything connected to the LAN interfaces on my sonicwall (X0) are getting the full 20Mbps (or really near with speedtest.net) but all my wireless clients only get up to 10Mbps...

Does anyone has any idea of what is going on here?

Thanks for your support

Network Analysis





Network analysis is the process of identifying and remediating the processes and systems within a network, including performance, connectivity and security. The process is performed through the use of tools developed for monitoring and analyzing network activity. Network problems that involve finding an optimal way of doing something are studied under the name combinatorial optimization. Examples include network flow, shortest path problem, transport problem, transshipment problem, location problem, matching problem, assignment problem, packing problem, routing problem, Critical Path Analysis and PERT (Program Evaluation & Review Technique).