Internet Protocol Security

Internet Protocol Security (IPsec) is a protocol suite for secure Internet Protocol (IP) communications by authenticating and encrypting each IP packet of a communication session. IPsec includes protocols for establishing mutual authentication between agents at the beginning of the session and negotiation of cryptographic keys to be used during the session. IPsec can be used in protecting data flows between a pair of hosts (host-to-host), between a pair of security gateways (network-to-network), or between a security gateway and a host (network-to-host). IPsec is an end-to-end security scheme operating in the Internet Layer of the Internet Protocol Suite.

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Digital Certificates have been a mystery to me.  I am starting to understand them better with more exposure to them; but....

 I want to understand how I can associate w Domain name for my work's Wireless Controller ( with the new Wireless controller?  Right now my manager uploaded something to the Wireless controller so I can type and arrive to the Wireless controller's administrator web page.

The same wireless controller provides a captive portal for Guest WiFi.  The Guest WiFi web portal currently shows https://Controller_IP_Address/cgi...welcome?  I would like to have the Domain_Name = Wlan/    show up in the web address instead of the Controller's IP address.

How can we make this happen?  I think we have a digital certificate; but, I think it is something that we created at the company.
Learn SQL Server Core 2016
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Learn SQL Server Core 2016

This course will introduce you to SQL Server Core 2016, as well as teach you about SSMS, data tools, installation, server configuration, using Management Studio, and writing and executing queries.

Example of Web Tokens

I am sure I have worked with these, but please give an overview.

Also, it would great if you could also include a .NET perspective

Can fortinet firewalls (50d) be setup to monitor an ipsec vpn connection and switch to another if one is down?
Using ADFS 3.0 additional authentication rules would the following be possible to create a rule that would do the following.

If OS = Android
And = IP address range is like 192.168.x.x as an example
Force Forms Authentication

If a device does not make this rule is would proceed with the normal Windows Integrated Authentication
I have a big problem with Cisco voip configuration. I have two CME router which is connected by IPsec over gre tunnel vpn. The flow between router Irak and router CI is correct but we can not make any calls, we heard a busy tone. However the calls between Router CI and Router Irak work well.
I don't know how to fix this issue. I need your help please.

Best Regards,
is there a proper way to establish connectivity between remote offices that are connected by VPN (SW SOHO) to the main branch that is using Sonicwalll NSA 2400. Each remote office has connectivity to the main branch, but need each remote office connectivity with each remote office via VPN.
Inherited a Cisco ASA and I have an IPSec tunnel configured and working great, however, I am trying to figure out which hosts are using this tunnel

Since the tunnel is encrypted, I can not seem to capture any packets

I see the peer ip for the tunnel, and the destination being the outside public ip of the ASA,  it need to the the host that is initiating this tunnel

Appreciate any insights, thanks
Cisco IPSec tunnel need to find out who is the final destination of a file copy through the tunnel
packet capture won’t show me the true destination host. I see the peer ip and destination is the public ip of the asa

Example user initiates a copy through the tunnel I am trying to identify which host is initiating this copy
I have about two dozen remote sites that I need to create VPN tunnel.  I have Checkpoint FW cluster here.  The 23 remote sites either have Cisco, Forcepoint, Palo Alto or Juniper firewalls.  Using IPSEC, I need a good plan for setting up individual tunnels to these disparate sites.  I have a general understanding of IPSEC but not the specifics for configuring each firewall.

Can you point me to good literature, or links, or video media that helps me lay out a plan for gathering all the information needed for/from each customer to roll out these VPNs?
Looking for a good detailed survey of SDWANs that are available and procedures how to deploy each,
If I have a worldwide client base and I need my staff to access customers' data centers privately, how do I pick the right SDWAN solution, and how to do I migrate to them?
Why Diversity in Tech Matters
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Kesha Williams, certified professional and software developer, explores the imbalance of diversity in the world of technology -- especially when it comes to hiring women. She showcases ways she's making a difference through the Colors of STEM program.

We have an IP sec tunnel setup between two locations, Once side is Cisco and the other a Fortigate. The ACL is setup to allow all traffic between the two locations. Most traffic does work but we found we are unable to pass SSH traffic through. We can see the SSH traffic leaving the Fortigate.  We have no problem connecting with SSH through the NAT statements on teh Cisco, so we know its the tunnel that is causing this. What am I missing?

crypto map chi-map 10 ipsec-isakmp
 description Tunnel to Chicago office
 set peer
 set security-association lifetime kilobytes disable
 set security-association lifetime seconds 43200
 set transform-set chi-ipsec
 set pfs group20
 match address 100

access-list 100 permit ip
WordPress site getting SPAMMED, not sure how to stop it.

My website,

has a Download button, and when you fill your Name and Email, then click the button, you get an email with the URL to my book's Preface and Chapter 1. Also, I get an email to my "info@" email's inbox with the name and email of the person requesting the downloading.

I am getting spammed there, by some sort of robot, and do not know how to stop it.

This started yesterday morning, and continued every few minutes, non-stop. I even added a CAPTA requirements this morning, but that had no impact.

How do I stop this SPAM?

Working to establish IPsec Site-to-Site VPN, the local network is 192.168.0.x behind a Cisco RV130W and far end has a Cisco NSA 2600 and also has a pre-existing VPN with the 192.168.0.x subnet. The tunnel needs to support a single host on each end.

Is it possible to assign a 2nd IP Address to the PC in my network, say, and use this for the VPN?
Morning, I am trying to setup a Windows 2016 VPN via LT2P but keep getting the below error.
Anyone know what I can do to fix it?

During main mode negotiation, IPsec received an invalid negotiation packet. If this problem persists, it could indicate a network issue or an attempt to modify or replay this negotiation.
Local Network Address:
Remote Network Address:
Keying Module Name:      IKEv1
How does password reset works in international locations with MFA.  Here in US I can input a phone number in AD Mobile field. example +1-415-111-1111
Then it sends a code to the phone and you confirm.  Would it work with international locations?  Example China +86-180-1111-1111
Internet (ISP) ----> CISCO 891 ----> Ubuntu Server [Another Country/City] (IPSec or smthing) ------]
                                                                                       Internet (ISP) <------ CISCO 891 <---------------------]

Can i configure the my home CISCO router to connect to another VPN Server and give access to my home computers to the internet from this Server?
Has been almost a year that I switch to Auth0 in order to manage my customer's access to the dashboard of my application. Nowadays I need to implement access for a RESTFULL API.

If I follow the instructions in order to secure the NodeJS app using JWT it works like a charm. The issue is that I am not properly sure on the implementation for the end user in order to get the token needed for access this API.

I thought of creating the tokens on the dashboard or just use a server side implementation for the login/authentication. I did the last using the access to my own database before and worker amazingly. My issue is that I am not completely sure on how to do it for the end user using Auth0.

Would be great if you can guide me in order to implement the login/authentication side of the API using auth0 and nodejs.
how I can know the imo and botim server block so I can blocked under my firewall ?
I have multiple sites on my internal network all connected with IPSec tunnels.   Each site has a Windows domain controller.  In addition to the domain controller, each site also has a NAS which serves as a file server.   My issue is this.    I want to publish a specific DNS name within one of the internal zones.   Assign each site a version of this name that points to the local NAS device.      I have all the IP information defined in sites and services.   When I have the DNS name something like I want the systems to return the IP of the local device.  What I'm seeing is from corporate, when I reference the device I'm getting random responses from across all of the offices.    
  Is there a way to make DNS prefer IP's on the site I sit on instead of round robin looking through the list of available servers?
Exploring ASP.NET Core: Fundamentals
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I have a problem to establish call session between two sites over gre tunnel ipsec. The tunnel is up but I am Unable to set a call. I think the problem is Nat but I don't know how to fix it.  It's seems like the traffic were blocked in the beginning of the tunnel.

You can see the configuration files in attached.


Best Regards,


Dear expert,

I have bought a Samsung smart TV. I am looking for trusted and secure IPTV to install it. And secure IPTV vendor including Bein Sport, OSN, US channels, UK BBC...etc

a friend of mine advice me to install KODI but it is showing on the samsung store.

Thank you in advance.
Hi guys

As part of the last question I asked about firewall rules, I am looking at our firewall right now and monitoring the traffic. I'm looking at the traffic between VPN connections from our stores to a main server. These stores are all using the same application to communicate with the server. However, I'm looking at the server and it is receiving connections from our various stores, but every single store is communicating via a different port. So one store will be coming through port 4274. The other one will send it via port 4288. My point is, are applications specifically written in this way to prevent security breaches from happening by constantly randomising their port sequences so that they can't be 'guessed' by a malicious attacker?

And if that is the case, surely going back to the answers being given previously, this does warrant the ability for the 'ANY' ports to be open from site A to site B via VPN.

Thank you
I have a watchguard M270, the customer has a hosted server they connect to via ipsec. What policy could I enable to allow the ipsec vpn outbound.
Hi all,
I have a FW problem,
I've got two fortigate firewalls connected by IPsec VPN which is working great. users can connect to the main site also with SSL VPN. The problem is that when an SSL VPN user can't get to the remote site computes,
The main site address is,
The remote site address is
The SSL VPN address is 172.16.0.(100-110).
The phase 2 in the IPsec VPN is configurd with and I've tried all the policies from the cookboos I could find but I still can't get it to work. The SSL Tunnel is split and the remote site address is configure in it.
What am I doing wrong?
Is there any suggestions on how can I resolve it?

Thanxs in advance

We  have  a network similar  to the diagram  shown above ,,
And  we  want  to configure IPSEC  IKv1 VPN between 2  sites .  we  have  A cisco  4321 Router at Branch A and  A Palo Alto firewall on  the  other end  …

After  doing  the well known configuration provided by Cisco at

we found  that  we  still could not  form  a successful a tunnel  between sites ,,   ..  
we  think that  there  a hope or a firewall somewhere in the  WAN path  blocking or  filtering
the  IKEv1  traffic  and  ICMP

so  the Questino consist of  two  parts :-

First :-   Kindly  provide  us  with  your suggestion regarding the proper an optimim configuration for the
Devices  at  both ends

Second :-   In  the  WAN  how  could  we  specify  the hop that  filter that traffic exactly ?
                          We  want  to prove that one hop is blocking or filtering IKv1 and ICMP traffic
              Then how could we find and prove that it  prevents specific data traffic  ?

Internet Protocol Security

Internet Protocol Security (IPsec) is a protocol suite for secure Internet Protocol (IP) communications by authenticating and encrypting each IP packet of a communication session. IPsec includes protocols for establishing mutual authentication between agents at the beginning of the session and negotiation of cryptographic keys to be used during the session. IPsec can be used in protecting data flows between a pair of hosts (host-to-host), between a pair of security gateways (network-to-network), or between a security gateway and a host (network-to-host). IPsec is an end-to-end security scheme operating in the Internet Layer of the Internet Protocol Suite.

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Internet Protocol Security