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Are you seeing this across the wire, from the client's perspective, or from the server's perspective? &nbsp;(where are you?)<br />
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Is the server side operating under normal conditions? (any DDOS underway?)
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A client might support one mode of Secure Communication (SSL1/23 and TLS) while the Server only supports the other (TLS 1.0). This is usually means that the server is not configured correctly.<br />

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I agree with Mod_MarlEE, seems like a homework question.<br />
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TLS V1 standard: <a href="http://www.ietf.org/rfc/rfc2246.txt" rel="ugc">http://www.ietf.org/rfc/rfc2246.txt</a><br />
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Baed on SSL V3, SSL was developed by NetScape TLS is the RCF'ed public version of SSL.<br />
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aikimark - I have two separate sniffs running to confirm that the network is behaving normally. One sniff is running on the client's local interface and the other is running on the switchport that the server is directly attached to. It is possible that the server is over-utilized.<br />
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arnold - This is my suspicion and specifically what I am attempting to isolate. The server's admin is convinced that it is not his machine, and I am thus attempting to understand the process so that I can help him troubleshoot it.<br />

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Here is a starting point for ssl inner workings.<br />
<a href="http://www.openssl.org/docs/ssl/ssl.html" rel="ugc">http://www.openssl.org/docs/ssl/ssl.html</a><br />
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The ssl_accept ssl_connect calls are the ones used to setup a connection.<br />
wiki.cacert.org is a site with a lot of infarmation esp. about trust around a certificate.
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Working under the knowledge that traffic is passing normally across a network...<br />
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What would cause SSL negotiation to break down between a client and server?<br />
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I have observed a client send a &quot;Client Hello&quot; to the server over SSL. Then the server sends an ACK for the &quot;Client Hello&quot; packet. However, the server fails to respond.<br />
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Approximately 30 seconds later, the client sends a &quot;Client Hello&quot; to the server via SSLv2. Then the server sends an ACK for the &quot;Client Hello&quot;. Then the server sends a &quot;Server Hello&quot; to the client via SSLv3.<br />
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Thoughts?
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Working under the knowledge that traffic is passing normally across a network...

What would cause SSL negotiation to break down between a client and server?

I have observed a client send a "Client Hello" to the server over SSL. Then the server sends an ACK for the "Client Hello" packet. However, the server fails to respond.

Approximately 30 seconds later, the client sends a "Client Hello" to the server via SSLv2. Then the server sends an ACK for the "Client Hello". Then the server sends a "Server Hello" to the client via SSLv3.

Thoughts?

What would cause a SSL negotiation to break down?

HTTPS is a protocol for secure communication over a computer network which is widely used on the Internet. HTTPS consists of communication over Hypertext Transfer Protocol (HTTP) within a connection encrypted by Transport Layer Security (TLS) or its predecessor, Secure Sockets Layer (SSL). The main motivation for HTTPS is authentication of the visited website and to protect the privacy and integrity of the exchanged data. HTTPS is widely used for protecting page authenticity on all types of websites, securing accounts and keeping user communications, identity and web browsing private.

SSL / HTTPS

Encryption is the process of encoding messages or information in such a way that only authorized parties can read it. In an encryption scheme, the intended communication information or message, referred to as plaintext, is encrypted using an encryption algorithm, generating ciphertext that can only be read if decrypted. For technical reasons, an encryption scheme usually uses a pseudo-random encryption key generated by an algorithm. An authorized recipient can easily decrypt the message with the key provided by the originator to recipients, but not to unauthorized interceptors.

Encryption

Security is the protection of information systems from theft or damage to the hardware, the software, and the information on them, as well as from disruption or misdirection of the services they provide. The main goal of security is protecting assets, and an asset is anything of value and worthy of protection.  Information Security is a discipline of protecting information assets from threats through safeguards to achieve the objectives of confidentiality, integrity, and availability or CIA for short. On the other hand, disclosure, alteration, and disruption (DAD) compromise the security objectives.