User manual

Complete ikesnoop command options can be found in the CLI Reference Guide.
The Client and the Server
The two parties involved in the tunnel negotiation are referred to in this section as the client and
server. In this context, the word "client" is used to refer to the device which is the initiator of the
negotiation and the server refers to the device which is the responder.
Step 1. Client Initiates Exchange by Sending a Supported Algorithm List
The verbose option output initially shows the proposed list of algorithms that the client first sends to
the server. This list details the protocols and encryption methods it can support. The purpose of the
algorithm list is that the client is trying to find a matching set of protocols/methods supported by the
server. The server examines the list and attempts to find a combination of the protocols/methods
sent by the client which it can support. This matching process is one of the key purposes of the IKE
exchange.
IkeSnoop: Received IKE packet from 192.168.0.10:500 Exchange type :
Identity Protection (main mode) ISAKMP Version : 1.0
Flags :
Cookies : 0x6098238b67d97ea6 -> 0x00000000
Message ID : 0x00000000
Packet length : 324 bytes
# payloads : 8
Payloads:
SA (Security Association)
Payload data length : 152 bytes
DOI : 1 (IPsec DOI)
Proposal 1/1
Protocol 1/1
Protocol ID : ISAKMP
SPI Size : 0
Transform 1/4
Transform ID : IKE
Encryption algorithm : Rijndael-cbc (aes)
Key length : 128
Hash algorithm : MD5
Authentication method : Pre-Shared Key
Group description : MODP 1024
Life type : Seconds
Life duration : 43200
Life type : Kilobytes
Life duration : 50000
Transform 2/4
Transform ID : IKE
Encryption algorithm : Rijndael-cbc (aes)
Key length : 128
Hash algorithm : SHA
Authentication method : Pre-Shared Key
Group description : MODP 1024
Life type : Seconds
Life duration : 43200
Life type : Kilobytes
Life duration : 50000
Transform 3/4
Transform ID : IKE
Encryption algorithm : 3DES-cbc
Hash algorithm : MD5
Authentication method : Pre-Shared Key
Group description : MODP 1024
Life type : Seconds
Life duration : 43200
9.4.5. Troubleshooting with ikesnoop Chapter 9. VPN
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