... cả các DNS data đã được relay bởi NAT Phần I:Giới thiệu tổng quan về NAT (Network Address Translation) I : NAT (Network Address Translation) là gì ?NAT giống như một router, nó chuyển tiếp ... truy tìm chỉ IP thì hoàn toàn không hiệu quả. Đó là trong các ứng dụng virtual server và virtual network bởi vì traffic được sinh ra bởi một IP thì không thể nào phân chia được nữa. Khi chúng ... thế cho nhiều host thật sự (real server) . Chúng ta cũng có thể tạo ra kết nối mạng ảo (virtual network) gồm nhiều mạch thật sự (real wire) dùng kỹ thuật virtual server. Chúng ta có thể làm điều...
... TRẢ LỜI BÀI TẬP ORACLECHƯƠNG 26ORACLE VÀ CẤU HÌNH MẠNG (ORACLE NETWORK CONFIGURATION)1. Listener là gì? Cáùc Service chính nào được dùng để phục cho việc truy...
... linkphysical network data linkphysical network data linkphysical network data linkphysical network data linkphysical network data linkphysical network data linkphysicalapplicationtransport network data linkphysicalapplicationtransport network data ... link Network Layer 4-11 Network layer connection and connection-less service❒datagram network provides network- layer connectionless service❒VC network provides network- layer connection ... layer❒ network layer protocols in every host, router❒Router examines header fields in all IP datagrams passing through it network data linkphysical network data linkphysical network data...
... KA-KDC(A,B)KA-KDC(R1, KB-KDC(A,R1) ) 8: Network Security8-2Chapter 8: Network SecurityChapter goals: ❒understand principles of network security: ❍cryptography and its many uses ... All Rights ReservedComputer Networking: A Top Down Approach Featuring the Internet, 3rd edition. Jim Kurose, Keith RossAddison-Wesley, July 2004. 8: Network Security8-47Key Distribution ... createa packet “spoofing”Alice’s address“I am Alice”Alice’s IP address 8: Network Security8-1Chapter 8 Network SecurityA note on the use of these ppt slides:We’re making these slides...
... Topic 3GWindown 2003 network securityTrong chủ đề này, bạn sẽ xem xét các tác động của biến bật / tắt các giao thức NetBIOS trên một máy Windown 2003.NetBIOS là viết tắt của Network Basic Input ... spooled để tăng tốc độ in ấn.17. Chọn Keep Printed Documents, và click OK.18. Nhấp đôi chuột vào My Network Places.19. Nhấp đôi chuột vào Computers Near Me.20. Nhấp đôi chuột vào printer server...
... network (serving network) to a terrestrial network orvice versa due to one of the reasons identified during the handover initiation phase.Handovers involved in two different but integrated networks ... networks. In designing a satellite network, the needfor inter-FES handover should be kept to a minimum.Integrated Satellite-Terrestrial Network Scenario In an integrated network, an on-goingcall may ... For a group usage terminal, accessto the network may still be maintained so that other users registered on this terminal can stillaccess the network. Network Procedures 235required. The path...
... Introduction to Networking Management3. Simple Network Management Protocol4. Network Security5. Outsourcing the Network I – Cloud Computing & SaaS6. Outsourcing the Network II – Green ... 10% (PF) + 50% (FE) • Sinh viên đậu khóa học khi: Tổng điểm ≥ 5 vàThi cuối môn học ≥ 5 (of 10) Network ManagementQuản trị hệ thống mạngVũ Trí Dũngdungvt@uit.edu.vnTài liệu tham khảo• Dùng ... Cloud Computing & SaaS6. Outsourcing the Network II – Green IT and SAN7. Managing Wireless Networks...
... supposed that 2 IP sub -network share physically the same LAN. The stations on eachsub -network then will see circulating all the packets diffused on the physic network. 1The network layerAddressing ... rentallease)7- Engineers network link: 2B-14-62-91-C9-B1- Engineers network link towards the external router: 2B-14-62-3F-39-21- Commercial network link: 1C-96-AA-F4-C2-91- Commercial network link towards ... 194.12.230.140.1. Propose a mask of sub -network for the network of company.194.12.230.0 is a Class C address, the last byte must be used to encode the numbers ofsub -network and the numbers of hosts...
... many false alarms Network Monitoring and Diagnostic Devices•SNMP enables network administrators to:–Monitor network performance–Find and solve network problems–Plan for network growth•Managed ... and network equipment –Can be used independently of the network and can have their own applications installed•Server: computer on a network dedicated to managing and controlling the network •Basic ... information and infecting the network Hardening Network Security Devices•The final category of network devices includes those designed and used strictly to protect the network •Include:–Firewalls–Intrusion-detection...
... giữa sáng kiến và hiệu quả của nóSAN solutionHợp nhất việc lưu trữ•SAN (Storage Area Network) và NAS (Network Attached Storage) là hai cách để tổ chức lại một hệ thống vào trong một nguồn ... chủ thông qua một card adapter, và thiết bị lưu trữ chỉ phục vụ cho một server duy nhất•NAS (network attached storage): là một dạng mạng LAN cơ bản chạy trên máy chủ file server sử dụng giao...
... Header checksumSource AddressDestination AddressOptionsDataAN TOÀN DỮ LIỆU TRÊN ĐƯỜNG TRUYỀN Network Security Course9m m’Trudy♦Making data un-readable by protocol analyzers and other “man-in-the-middle” methods on the network. AliceBobBÀI TẬP 4Sau khi dùng Sniffing software để bắt thông tin phân tích gói thông tin gửi đi từ host AGói 1: Protocol ... description0 0 echo reply (ping)3 0 dest. network unreachable3 1 dest host unreachable3 2 dest protocol unreachable3 3 dest port unreachable3 6 dest network unknown3 7 dest host unknown4 ... nhập6. Kỹ Thuật Mã hóa7. Hệ thống xác thực8. Virtual Private Networks9. Kỹ Thuật tấn công10. Luật, chính sách an toàn thông tin11 Network Security CourseCƠ BẢN VỀ AN NINH MẠNG CƠ BẢN VỀ AN NINH MẠNG Các...
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SUMMARYVPNs do not make use of dedicated leased linesVPNs send data through a secure tunnel that leads from one endpoint to another VPNs keep critical business communications private and secureVPN componentsVPN serversVPN clientsProtocols39TUNNELING PROTOCOLSLayer 2 Tunneling Protocol (L2TP)Provides better security through IPSecIPSec enables L2TP to performAuthenticationEncapsulationEncryption18TUNNELING PROTOCOLSSecure Shell (SSH)Provides authentication and encryptionWorks with UNIXbased systemsVersions for Windows are also availableUses publickey cryptographySocks V. 5Provides proxy services for applications That do not usually support proxyingSocks version 5 adds encrypted authentication and support for UDP2016ENCRYPTION SCHEMES USED BY VPNS (CONTINUED)Secure Sockets Layer (SSL) (continued)StepsServer uses its private key to decode premaster codeGenerates a master secret keyClient and server use it to generate session keysServer and client exchange messages saying handshake is completedSSL session begins34SUMMARY (CONTINUED)VPN typesSitetositeClienttositeEncapsulation encloses one packet within another Conceals the original informationVPN protocolsSecure Shell (SSH)Socks version 5PointtoPoint Tunneling Protocol (PPTP)Layer 2 Tunneling Protocol (L2TP)40Virtual Private Network (VPN) 29BIếN ĐổI ĐÓNG GÓI TRONG VPN (ENCAPSULATION)Các buớc trong tiến trình VPN Đóng gói (Encapsulation)Mã hoá (Encryption)Xác thực (Authentication)EncapsulationĐóng gói dữ liệu và các thông số khác nhauVí dụ như IP headerBảo vệ tính nguyên vẹn dữ liệu153127VPN CORE ACTIVITY 2: ENCRYPTIONEncryptionProcess of rendering information unreadable by all but the intended recipientComponentsKeyDigital certificateCertification Authority (CA)Key exchange methodsSymmetric cryptographyAsymmetric cryptographyInternet Key ExchangeFWZ2812SUMMARY (CONTINUED)IPSec/IKEEncryption makes the contents of the packet unreadableAuthentication ensures participating computers are authorized usersKerberos: strong authentication systemVPN advantagesHigh level of security at low costVPN disadvantagesCan introduce serious security risks412410255ENCRYPTION SCHEMES USED BY VPNSTriple Data Encryption Standard (3DES)Used by many VPN hardware and software3DES is a variation on Data Encryption Standard (DES)DES is not secure3DES is more secureThree separate 64bit keys to process data3DES requires more computer resources than DES30WHY ESTABLISH A VPN?VPN combinationsCombining VPN hardware with software adds layers of network securityOne useful combination is a VPN bundled with a firewallVPNs do not eliminate the need for firewallsProvide flexibility and versatility13FIREWALL CONFIGURATION FOR VPNS37Protocol ... SUMMARYVPNs do not make use of dedicated leased linesVPNs send data through a secure tunnel that leads from one endpoint to another VPNs keep critical business communications private and secureVPN componentsVPN serversVPN clientsProtocols39TUNNELING PROTOCOLSLayer 2 Tunneling Protocol (L2TP)Provides better security through IPSecIPSec enables L2TP to performAuthenticationEncapsulationEncryption18TUNNELING PROTOCOLSSecure Shell (SSH)Provides authentication and encryptionWorks with UNIXbased systemsVersions for Windows are also availableUses publickey cryptographySocks V. 5Provides proxy services for applications That do not usually support proxyingSocks version 5 adds encrypted authentication and support for UDP2016ENCRYPTION SCHEMES USED BY VPNS (CONTINUED)Secure Sockets Layer (SSL) (continued)StepsServer uses its private key to decode premaster codeGenerates a master secret keyClient and server use it to generate session keysServer and client exchange messages saying handshake is completedSSL session begins34SUMMARY (CONTINUED)VPN typesSitetositeClienttositeEncapsulation encloses one packet within another Conceals the original informationVPN protocolsSecure Shell (SSH)Socks version 5PointtoPoint Tunneling Protocol (PPTP)Layer 2 Tunneling Protocol (L2TP)40Virtual Private Network (VPN) 29BIếN ĐổI ĐÓNG GÓI TRONG VPN (ENCAPSULATION)Các buớc trong tiến trình VPN Đóng gói (Encapsulation)Mã hoá (Encryption)Xác thực (Authentication)EncapsulationĐóng gói dữ liệu và các thông số khác nhauVí dụ như IP headerBảo vệ tính nguyên vẹn dữ liệu153127VPN CORE ACTIVITY 2: ENCRYPTIONEncryptionProcess of rendering information unreadable by all but the intended recipientComponentsKeyDigital certificateCertification Authority (CA)Key exchange methodsSymmetric cryptographyAsymmetric cryptographyInternet Key ExchangeFWZ2812SUMMARY (CONTINUED)IPSec/IKEEncryption makes the contents of the packet unreadableAuthentication ensures participating computers are authorized usersKerberos: strong authentication systemVPN advantagesHigh level of security at low costVPN disadvantagesCan introduce serious security risks412410255ENCRYPTION SCHEMES USED BY VPNSTriple Data Encryption Standard (3DES)Used by many VPN hardware and software3DES is a variation on Data Encryption Standard (DES)DES is not secure3DES is more secureThree separate 64bit keys to process data3DES requires more computer resources than DES30WHY ESTABLISH A VPN?VPN combinationsCombining VPN hardware with software adds layers of network securityOne useful combination is a VPN bundled with a firewallVPNs do not eliminate the need for firewallsProvide flexibility and versatility13FIREWALL CONFIGURATION FOR VPNS37Protocol ... 1723TUNNELING PROTOCOLSPointtoPoint Tunneling Protocol (PPTP)Used when you need to dial in to a server with a modem connectionOn a computer using an older OS versionEncapsulates TCP/IP packetsHeader contains only information needed to route data from the VPN client to the serverUses Microsoft PointtoPoint Encryption (MPPE)Encrypt data that passes between the remote computer and the remote access serverL2TP uses IPSec encryptionMore secure and widely supported17NỘI DUNGNguyên lý VPNCác biến đổi đóng gói trong VPNsMã hoá trong VPNsXác thực trong VPNsƯu nhược điểm của VPNs2VPN CORE ACTIVITY 3: AUTHENTICATIONAuthenticationIdentifying a user or computer as authorized to access and use network resourcesTypes of authentication methods used in VPNsIPSecMSCHAPBoth computers exchange authentication packets and authenticate one anotherVPNs use digital certificates to authenticate users35...