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Questions tagged [tcpip]

TCP and IP are two important protocols used in networking today. Due to their importance, the Internet Protocol Suite is also commonly known as "TCP/IP"

464 questions
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192.168.1.x more exploitable?

Our IT services firm is proposing a network reconfiguration to use the IP range 10.10.150.1 – 10.10.150.254 internally as they state the current IP scheme using manufacturer defaults of 192.168.1.x is "making it to easy to exploit". Is this true?…
Michael Glenn
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How does the HTTP GET method work in relation to DNS protocol?

I am trying to understand application layer protocols in TCP/IP stack. I know that both HTTP and DNS protocol stay at the top layer (Application Layer). So, when a browser wants to access a resource, it has to send a request to the HTTP server, as…
Giancarlo Perlo
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What is the OSI model and how does it apply to todays networks?

As a system administrator what should I know about the OSI model? (Rec X.200) Briefly, what are the layers and what do they do? How much do I need to know about in my day-to-day work? How does this contrast with the TCP/IP model? (RFC1122) Does the…
Zoredache
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How is the MTU is 65535 in UDP but ethernet does not allow frame size more than 1500 bytes

I am using a fast ethernet of 100 Mbps, whose frame size is less than 1500 bytes (1472 bytes for payload as per my textbook). In that, I was able to send and receive a UDP packet of message size 65507 bytes, which means the packet size was 65507 +…
nikku
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2 answers

What is [PSH, ACK] doing during my connection to a global catalog server?

A linux server of mine is trying to establish a LDAPS connection to a global catalog server and the connection is getting dropped (presumably by the GC side). For the purpose of discussion, let's say that 1.1.1.1 is the Linux server and 1.2.3.4 is…
Mike B
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When IP aliasing how does the OS determine which IP address will be used as source for outbound TCP/IP connections?

I have a server running Ubuntu Server with four IP addresses aliased on a single NIC. eth0 192.168.1.100 eth0:0 192.168.1.101 eth0:1 192.168.1.102 eth0:2 192.168.1.103 (Using 192.168.x.x for sake of example, assume these are…
Joe Holloway
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How are IP addresses actually assigned?

I'm having a hard time understanding how a governing body assigns IP addresses, companies use BGP to advertise those IPs, and how the internet works. Then, where the hell does DNS come in? Can anyone suggest a good read of how this stuff actually…
Vegim
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What do all the settings in the Advanced TCP/IP Properties DNS Tab Mean?

Can someone explain TCT/IP > Properties > Advanced > 'DNS' tab please? I know what DNS, primary DNS suffix and DNS suffix are, but this tab has some confusing properties.
Dean
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What am I misunderstanding about calculating MTU?

Okay, I just finished resolving a jumbo frames issue between a few Xserves, a Netgear GSM7224, and a Drobo B800i. It turned out that the Xserves (Mac OS X 10.6.8 Server) and the Drobo B800i accept the MTU in bytes as normally expected (1500-9000),…
morgant
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AWS flagged my subnet as invalid although it looks to be within the VPC CIDR block

My VPC CIDR block is 10.0.0.0/16 As I understand it, this should support 256 (effectively 254) subnets with 65534 hosts per subnet. When I tried to create one subnet 10.8.0.0/24 and associate it with the VPC, I received this error: Error creating…
Bon Ami
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Tuning NFS client/server stack

I have a CentOS 5 VMWare server connecting to an OpenSolaris 2009.06 machine over NFS that holds the disk images. My virtual machines seem to be bound by slow IO so I'd like to do everything I can to optimize the connection. I'm not sure of the…
Sysadminicus
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Slash Notation IP - What is what?

We just signed up with a new ISP and we got a static IP from them. Our previous ISP just gave one IP and we were able to configure our web server using that. Now, we have got this new IP with a slash notation. This type is new to me. When I used the…
Nirmal
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How do I view the TCP Send and Receive Queue sizes on Windows?

Linux netstat shows send and receive queue sizes. How do I get this info under Windows, specifically Server 2003?
Brien
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Where is the documentation that states TCP and UDP source port should be over 1024 and random?

I am having a hard time to find where it is documented that the source port should be random and in the range 1024-65535. In which RFC is this documented? Edit: First reference for privileged ports is in RFC2623 It seems that this is depending more…
Mircea Vutcovici
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What is the maximum number of TCP connections I can have in Windows Server 2008?

I would like to have as many connections (single connections from many different clients) as humanly possible in a server running on Windows Server 2008, in order to support a Comet-style application. The application is written in C#. The…
evilfred
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