I will show a little tricky thing about Layer 3 communication between different vlans.

Given the following figure.

So it is a very silly thing. On SW1 you have configured vlan30 for port fa0/1 and fa0/2.
On Switch SW2 you have configured Vlan20 for port fa0/3 and fa0/1.

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Cisco NTP basics

NTP is a protocol designed to synchronize clock with a atomic- or a radio clock.
The NTP Protocol uses the current standard of protocol version 4.
NTP is reserved for the UDP-Port 123.
The timestamp at NTP are 64bit long. 32 bits encode the seconds since the beginning of 1. Januar 1900 00:00:00. The next 32 bits are the fraction of the seconds.
With this manner it is possible to calculate the time in a resolution of 2 ^-32 seconds.

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Now i want to show how to configure a IPSec Remote-Access with an ASA5505.
Given is a DSL-Modem(NTBBA) and an ASA5505 with a Software Image <=8.3.

1. Prepare the ASA for the WAN connection.

In this section you learn how to configure the ASA5505 to get a connection to the WAN.
We used the Interface Vlan1 to connect with the DSL-Modem. Please set the DSL-Modem to
‘Pass-through Mode’.

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