... SUMMARY
VPNs do not make use of dedicated
leased lines
VPNs send data through a secure tunnel
that leads from one endpoint to another
VPNs keep critical business
communications private and secure
VPN components
VPN servers
VPN clients
Protocols
39
TUNNELING PROTOCOLS
Layer 2 Tunneling Protocol (L2TP)
Provides better security through IPSec
IPSec enables L2TP to perform
Authentication
Encapsulation
Encryption
18
TUNNELING PROTOCOLS
Secure Shell (SSH)
Provides authentication and encryption
Works with UNIXbased systems
Versions for Windows are also available
Uses publickey cryptography
Socks V. 5
Provides proxy services for applications
That do not usually support proxying
Socks version 5 adds encrypted authentication and
support for UDP
20
16
ENCRYPTION SCHEMES USED BY
VPNS (CONTINUED)
Secure Sockets Layer (SSL) (continued)
Steps
Server uses its private key to decode premaster code
Generates a master secret key
Client and server use it to generate session keys
Server and client exchange messages saying handshake is
completed
SSL session begins
34
SUMMARY (CONTINUED)
VPN types
Sitetosite
Clienttosite
Encapsulation encloses one packet within
another
Conceals the original information
VPN protocols
Secure Shell (SSH)
Socks version 5
PointtoPoint Tunneling Protocol (PPTP)
Layer 2 Tunneling Protocol (L2TP)
40
Virtual PrivateNetwork
(VPN)
29
BIếN ĐổI ĐÓNG GÓI TRONG VPN
(ENCAPSULATION)
Các buớc trong tiến trình VPN
Đóng gói (Encapsulation)
Mã hoá (Encryption)
Xác thực (Authentication)
Encapsulation
Đóng gói dữ liệu và các thông số khác nhau
Ví dụ như IP header
Bảo vệ tính nguyên vẹn dữ liệu
15
31
27
VPN CORE ACTIVITY 2: ENCRYPTION
Encryption
Process of rendering information unreadable
by all but the intended recipient
Components
Key
Digital certificate
Certification Authority (CA)
Key exchange methods
Symmetric cryptography
Asymmetric cryptography
Internet Key Exchange
FWZ
28
12
SUMMARY (CONTINUED)
IPSec/IKE
Encryption makes the contents of the
packet unreadable
Authentication ensures participating
computers are authorized users
Kerberos: strong authentication system
VPN advantages
High level of security at low cost
VPN disadvantages
Can introduce serious security risks
41
24
10
25
5
ENCRYPTION SCHEMES USED BY
VPNS
Triple Data Encryption Standard (3DES)
Used by many VPN hardware and software
3DES is a variation on Data Encryption Standard
(DES)
DES is not secure
3DES is more secure
Three separate 64bit keys to process data
3DES requires more computer resources than DES
30
WHY ESTABLISH A VPN?
VPN combinations
Combining VPN hardware with software adds
layers of network security
One useful combination is a VPN bundled with a
firewall
VPNs do not eliminate the need for firewalls
Provide flexibility and versatility
13
FIREWALL CONFIGURATION FOR
VPNS
37
Protocol ... 1723
TUNNELING PROTOCOLS
PointtoPoint Tunneling Protocol (PPTP)
Used when you need to dial in to a server with
a modem connection
On a computer using an older OS version
Encapsulates TCP/IP packets
Header contains only information needed to
route data from the VPN client to the server
Uses Microsoft PointtoPoint Encryption
(MPPE)
Encrypt data that passes between the remote computer
and the remote access server
L2TP uses IPSec encryption
More secure and widely supported
17
NỘI DUNG
Nguyên lý VPN
Các biến đổi đóng gói trong VPNs
Mã hoá trong VPNs
Xác thực trong VPNs
Ưu nhược điểm của VPNs
2
VPN CORE ACTIVITY 3:
AUTHENTICATION
Authentication
Identifying a user or computer as authorized to
access and use network resources
Types of authentication methods used in VPNs
IPSec
MSCHAP
Both computers exchange authentication packets and
authenticate one another
VPNs use digital certificates to authenticate users
35
... SUMMARY
VPNs do not make use of dedicated
leased lines
VPNs send data through a secure tunnel
that leads from one endpoint to another
VPNs keep critical business
communications private and secure
VPN components
VPN servers
VPN clients
Protocols
39
TUNNELING PROTOCOLS
Layer 2 Tunneling Protocol (L2TP)
Provides better security through IPSec
IPSec enables L2TP to perform
Authentication
Encapsulation
Encryption
18
TUNNELING PROTOCOLS
Secure Shell (SSH)
Provides authentication and encryption
Works with UNIXbased systems
Versions for Windows are also available
Uses publickey cryptography
Socks V. 5
Provides proxy services for applications
That do not usually support proxying
Socks version 5 adds encrypted authentication and
support for UDP
20
16
ENCRYPTION SCHEMES USED BY
VPNS (CONTINUED)
Secure Sockets Layer (SSL) (continued)
Steps
Server uses its private key to decode premaster code
Generates a master secret key
Client and server use it to generate session keys
Server and client exchange messages saying handshake is
completed
SSL session begins
34
SUMMARY (CONTINUED)
VPN types
Sitetosite
Clienttosite
Encapsulation encloses one packet within
another
Conceals the original information
VPN protocols
Secure Shell (SSH)
Socks version 5
PointtoPoint Tunneling Protocol (PPTP)
Layer 2 Tunneling Protocol (L2TP)
40
Virtual PrivateNetwork
(VPN)
29
BIếN ĐổI ĐÓNG GÓI TRONG VPN
(ENCAPSULATION)
Các buớc trong tiến trình VPN
Đóng gói (Encapsulation)
Mã hoá (Encryption)
Xác thực (Authentication)
Encapsulation
Đóng gói dữ liệu và các thông số khác nhau
Ví dụ như IP header
Bảo vệ tính nguyên vẹn dữ liệu
15
31
27
VPN CORE ACTIVITY 2: ENCRYPTION
Encryption
Process of rendering information unreadable
by all but the intended recipient
Components
Key
Digital certificate
Certification Authority (CA)
Key exchange methods
Symmetric cryptography
Asymmetric cryptography
Internet Key Exchange
FWZ
28
12
SUMMARY (CONTINUED)
IPSec/IKE
Encryption makes the contents of the
packet unreadable
Authentication ensures participating
computers are authorized users
Kerberos: strong authentication system
VPN advantages
High level of security at low cost
VPN disadvantages
Can introduce serious security risks
41
24
10
25
5
ENCRYPTION SCHEMES USED BY
VPNS
Triple Data Encryption Standard (3DES)
Used by many VPN hardware and software
3DES is a variation on Data Encryption Standard
(DES)
DES is not secure
3DES is more secure
Three separate 64bit keys to process data
3DES requires more computer resources than DES
30
WHY ESTABLISH A VPN?
VPN combinations
Combining VPN hardware with software adds
layers of network security
One useful combination is a VPN bundled with a
firewall
VPNs do not eliminate the need for firewalls
Provide flexibility and versatility
13
FIREWALL CONFIGURATION FOR
VPNS
37
Protocol...
... - In LuËn v¨n, TiÓu luËn
: 6.280.688
Lý thuyết.
I. Tổng quan về mạng riêng ảo VPN (Virtual Private Network) .
II. VPN và bảo mật internet VPN.
III. Thiết kế VPN
I. Tổng quan về mạng riêng ... tiết kiệm
được chi phí và thời gian. VPN ra đời đáp ứng tất cả các yêu cầu trên
Cụm từ VirtualPrivateNetwork gọi là mạng riêng ảo- VPN được khởi sự
năm 1997.
Mục đích mong muốn của công nghệ ... nào dựa trên PPTP triển khai ít nhất 3
thành phần, các thành phần đó là :
- PPTP client
- NetworkAccess Server (NAS)
- PPTP server
23
CH sè 11 - B1 - §H KTQD Chuyªn Photocopy - §¸nh m¸y -...
... hai loại phổ biến hiện nay là VPN truy cập từ xa (Remote -Access )
và VPN điểm-nối-điểm (site-to-site).
1. VPN Remote Access
- Remote Access VPNs cho phép truy cập bất cứ lúc nào bằng Remote,
mobile, ... tunnel về mạng của họ.
I. Giới Thiệu VPN
1. Khái niệm
- Mạng riêng ảo hay VPN (viết tắt cho VirtualPrivate Network) là một
mạng dành riêng để kết nối các máy tính của các công ty, tập đoàn hay các ... lại đóng vai
_________________________________________________________________________
VIRTUAL PRIVATENETWORK (VPN)
Nhóm 18
Lớp: DHTH3
GV: Th.s Nguyễn Hòa
Danh sách:
1. Đặng Hồng Hải
2. Hồ Thanh...
... Thí nghiệm TTDL & Mạng máy tính
Trang 55
9. Nhấn Next. Trên trang Network Connection, chọn VirtualPrivateNetwork
connection.
10. Nhấn Next. Trên trang Connection Name, gõ VPN Client ... and Remote Access nhấn vào Remote Access Policies
nhấn chuột phải vào Connections to Microsoft Routing and Remote Access server chọn
Properties. Trên thẻ Setting chọn Grant remote access permission. ... Routing and Remote Access Server Setup nhấn Finish
Tiếp theo ta cấu hình giao diện quay số yêu cầu
1. Trên Routing and Remote Access chọn SIM01 và nhấn chuột phải vào network
Interface...
... services to keep your network safe. However, most modern VPN
systems are combined with firewalls in a single device.
Virtual Private Networking Explained
Virtual Private Networks solve the problem ... gain local access to the laptop,
and discovers that it is automatically connecting to a remote network via IPSec. This provides the
hacker remote access to the private network, so he uses network ... of LAN communications, including file and print access, LAN
e mail, Remote Procedure Calls, and client/server database access. −
Virtual Private Networks between LANs can be established using server...
... 3
F
or more restrictive access to the network, NAP can be set up to restrict or limit access to the private network,
while permitting access to a restricted area of the network, and automatically ... health policy. Then, private network
access will be granted.
Four Features of NetworkAccess Protection
1. Health Policy Validation
When a user attempts to connect to a network, the computer’s ... net
-
work access and communication.
Network Access Protections is also known as a network quarantine platform from Microsoft that isolates a
computer that might be a danger to your network until...
... segments or between
the privatenetwork and public networks.
Placing Routers Within the PrivateNetwork
You need to place routers within the privatenetwork so that:
The network traffic is isolated ... and Remote Access filters restrict:
Internet access to privatenetwork resources, such as servers.
Private network user access to Internet-based resources, such as partner
networks or ... Internet, and other privatenetwork locations. Restricting
the traffic enables you to limit user access between privatenetwork segments,
and limit Internet user access to privatenetwork segments....
... permit others access, or restrict one
or more users from accessing a specific website. Define access restrictions with the access- list
command, and use the access- group command to bind the access- list ... 3 Controlling NetworkAccess and Use
Simplifying Access Control with Object Grouping
Configuring Network Object Groups
This section describes the commands required to configure a network object ... 7
(Optional) Use the show access- list command to display the expanded access list entries:
pix(config)# show access- list
access- list acl permit tcp host 201.165.201.1 host 1.1.1.1
access- list acl permit...
... public
internetwork in a manner that emulates the properties of a point-to-point private link.
The act of configuring and creating a virtualprivatenetwork is known as virtual
private networking. ... the internetwork appears to
the user as a privatenetwork communication—despite the fact that this
communication occurs over a public internetwork—hence the name virtualprivate
network.
VPN ... creation of VPNs from anywhere, networks need
strong security features to prevent unwelcome access to private networks and to
protect private data as it traverses the public network. User authentication...
... Next để tiếp tục
Bước 2: Chạy VZACCESS MANAGER SETUP WIZARD
Kích Start để chuyển tới menu VZAccess Manager để bắt đầu chương trình VZAccess
Manager.
Lần đầu tiên VZAccess Manager chạy, Setup Wizard ... Card
Chạy VZAccess Manager (nếu chưa được khởi động). Cửa sổ ứng dụng VZAccess
Manager sẽ được hiển thị. Chọn một trong số những kết nối sau: "NationalAccess",
"NationalAccess - ... phần mềm
VZAccess Manager vào, một số lựa chọn được hiển thị. Tại thời điểm này, bạn có thể
tiếp tục cài đặt hoặc thoát cài đặt VZAccess Manager. Nếu bạn không có đĩa CD phần
mềm VZAccess Manager,...
... between the L2TP Network Server (LNS), and the L2TP Access Concentrator (LAC). The LNS
typically runs on a network gateway such as a router, while the LAC can be a dial-up Network Access
Server ... Client Overview
Remote access VPN users employing the Cisco VPN 3000 Client version 2.5/2.6, or the Cisco VPN
Client version 3.x, can now securely access their private enterprise network through the ... 14
Create an access list that defines the PIX Firewall network( s) requiring IPSec protection:
access- list 90 permit ip 10.0.0.0 255.255.255.0 10.1.1.0 255.255.255.0
Step 15
Bind the access list...
... trên enforcement client.
Những gì NetworkAccess Protection không thể thực hiện được là ở chỗ, nó
không thể tránh được các kẻ xâm phạm bừa bãi vào mạng. NetworkAccess
Protection chỉ bảo đảm rằng ... các tổ chức, tuy nhiên lại không thay thế được các cơ
chế bảo mật khác mà bạn đang sử dụng. NetworkAccess Protection không thỏ
a
mãn được sự hài lòng trong trường hợp bảo đảm các máy khách từ ... các máy trạm đang được sử dụng cho việc truy cập
từ xa có đủ các tiêu chuẩn. Chính vì vậy, NetworkAccess Protection sẽ chỉ ngăn
được hacker nếu máy tính không thỏa mãn chính sách an ninh mạng...