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Unfortunately, the only way to make such a router without wireless idiot proof a default device settings complex that the user needs to use a parameter to one of the other wireless hardware change. By extension, this means that each wireless device can connect with said router with the default settings.

Again, this means that all wireless devices within range can connect to the new Smith router. Now, if you're Joe Smith, do you have something you want to hide?

There are a few reasons why wireless networks are less secure than their wired counterparts. First, there is the fact of their physical nature. They are wireless, transmission of a signal over an area. Each computer in this field with the right equipment can be considered "connected" to the network.

No similar access easier son to the network for everyone. This also makes it one of the most popular hacking tactics lot easier: packet sniffing or capturing network traffic for analysis for more information. Anyone coming within range can receive all traffic on the wireless network.

Second, the current methods of security technology without most available wireless, 802.11b, or easy to beat or difficult to implement.

The two most common methods for secure 802.11b WEP (Wireless Encryption Protocol) and MAC address filtering. WEP (64-bit or 128-bit) to protect wireless traffic using a key to encrypt the data shared between all computers that need access. WPA (WiFi Protected Access), which is now just beginning to emerge, treat all Weps gaps, so we'll go into a little later in the guide.

To disable Telnet and enable only SSH connections:

First login to the Cisco Switch or Router and enter configuration mode

Router# config t

Router1(config)# line vty 0 4

Router1(config-line)# transport input ssh

This disables telnet and enables ssh on all the five VTYs (Virtual Terminal Lines)

On earlier platforms five simultaneous remote connections are allowed and these are vty 0 to 4. On IOS 12.2 and up 16 simultaneous connections are allowed. On these

Router1(config)# line vty 0 15

Router1(config-line)# transport input ssh

This disables telnet and enables ssh on all the 16 VTYs.

Sometimes you want to disable all forms of remote access (Telnet and SSH). For this

Router1(config)# line vty 0 4

Router1(config-line)# transport input none

Or

Router1(config)# line vty 0 15

Router1(config-line)# transport input none

After this you can only connect to your Cisco device by direct console connection.

To enable Telnet and SSH back

Router1(config)# line vty 0 4

• Summary LSAs for ABRs (Type 3)— These LSAs advertise internal networks to routers in other areas, called OSPF interarea routes. The LSA might contain a summary network or a single network. ABRs are the only router type that generates this LSA type. OSPF represents these routes in the forwarding table with an O IA.

Q4. What is the difference between an OPPF neighbor and an adjacent neighbor? Ans. Neighbors are the routers that are in the same area and exchange hello packets, but not LSA information. Adjacent routers are routers that have fully exchanged their LSA information and are stable. If OSPF state is in 2WAY/DROTHER, it means a neighbor relationship and, if the state is FULL/DR or FULL/BDR, it means that the adjacency is formed.

Q5. What is the difference between standard and extended ACL? Ans. Standard ACLs are source-based, whereas extended ACLs are source- and destination-based. Standard ACLs can only filter layer 3 network traffic, while extended ACLs can be used to filter layer 3 and layer 4, as well.

Q6. What is the use of distribute-list? Ans. To filter a routing database, we use distribute-list, which can be applied over most routing protocols. This means that, If you don’t want any specific network in your routing table, then you can use distribute-list

Q7. What are broadcast domains? Ans. A broadcast domain defines a group of devices that receive each others' broadcast messages. As with collisions, the more broadcasts that occur on the network, the slower your network will be. This is because every device that receives a broadcast must process it to see if the broadcast is intended for it.

Q8. What is the difference between a routing protocol and a routed protocol? Ans. Routing protocols determine how to route traffic to the best location of a routed protocol. Examples of routing protocols are RIP, EIGRP, OSFP, and BGP. Examples of routed protocols are IP and IPX.

Q9. What is the destination address of broadcast frames? Ans. The destination address of broadcast frames (Layer 2 broadcast addresses) is FF-FF-FF-FF-FF-FF, or all 1s in binary.

Q10. What is the Spanning-Tree Protocol (STP)? Ans. STP is a loop-prevention bridge-to-bridge protocol. Its main purpose is to dynamically maintain a loop-free network. It does this by sending out Bridge Protocol Data Units (BPDUs), discovering any loops in the topology, and blocking one or more redundant links.

Q11. In spanning tree, what is a Bridge ID (BID)? Ans. A BID is an 8-byte field that is composed of the bridge's 6-byte MAC address and a 2-byte bridge priority.

Q12. In.In spanning tree, what is path cost? Ans. Path cost is a calculation to determine the link's bandwidth. It is a value assigned to each port that is based on the port's speed.

Q13. What is the STP blocking state? Ans. When a switch starts, all ports are in the blocking state. This is to prevent any loops in the network. If there is a better path to the root bridge, the port remains in the blocked state. Ports in the blocked state cannot send or receive traffic, but they can receive BPDUs.

Q14. What is the STP listening state? Ans. Ports transition from a blocked state to a listening state. In this state, no user data is passed. The port only listens for BPDUs. After listening for 15 seconds (if the bridge does not find a better path), the port moves to the next state, the learning state.

Q-3: What are FMSO Roles?  Fsmo roles are server roles in a Forest There are five types of FSMO roles 1-Schema master 2-Domain naming master 3-Rid master 4-PDC Emullator 5-Infrastructure master

Q-4: What is LMHOSTS file? It’s a file stored on a host machine that is used to resolve NetBIOS to specific IP addresses.

Q-5: What is ARP?  ARP is used to resolve a known IP address to a MAC address. For a host to communicate with another host, it must know the MAC address of the destination host (if they are on the same network) or next-hop router. This is the reason for ARP.

Q-6: What is APIPA?  (Automatic Private IP Addressing) The Windows function that provides DHCP auto configuration addressing. APIPA assigns a class B IP address from 169.254.0.0 to 169.254.255.255 to the client when a DHCP server is either permanently or temporarily unavailable. Designed for small non-routable networks, if a DHCP server becomes available later, the APIPA address is replaced with one from the DHCP server. For example, when a Windows Vista machine starts up, it waits only six seconds to find a DHCP server before assigning an IP from the APIPA range. It then continues to look for a DHCP server. Previous versions of Windows looked for a DHCP server for up to three minutes. See DHCP auto configuration addressing, DHCP and private IP address.

Q-7: What ports are used by DHCP and the DHCP clients?  Requests are on UDP port 68, Server replies on UDP 67

Q-8: DNS zones - describe the differences between the 4 types.  i)Forward Lookup Zones :-

This zone is responsible to resolve host name to ip.

ii)Reverse Lookup Zones :-

This zone is responsible to resolve ip to host name.

iii)Stub Zone :-

Stubzone is read only copy of primary zone.but it contains only 3 records the SOA for the primary zone, NS record and a Host (A) record.

Q-9: DNS record types - describe the most important ones. Type of Record What it does  A (Host) Classic resource record. Maps hostname to IP(ipv4)

PTR Maps IP to hostname (Reverse of A (Host)

AAAA Maps hostname to ip (ipv6)

Cname Canonical name, in plain English an alias.such as Web Server,FTP Server, Chat Server

NS Identifies DNS name servers. Important for forwarders

MX Mail servers, particularly for other domains.MX records

Q-10: What is Domain Controller? A domain controller (DC) or network domain controller is a Windows-based computer system that is used for storing user account data in a central database. It is the center point of the Windows Active Directory service that authenticates users, stores user account information and enforces security policy for a Windows domain. A domain controller allows system administrators to grant or deny users access to system resources, such as printers, documents, folders, network locations, etc., via a single username and password.

Q-11: What is Group Policy? Group Policy allows you to implement specific configurations for users and computers. Group Policy settings are contained in Group Policy objects (GPOs), which are linked to the following Active Directory service containers: sites, domains, or organizational units (OUs).

Q-12: What are GPOs (Group Policy Objects)? A Group Policy Object (GPO) is a collection of settings that control the working environment of user accounts and computer accounts. GPOs define registry-based policies, security options, software installation and maintenance options, script options, and folder redirection options.

Q-13: Where is the AD database stored? The AD database is stored in C:\Windows\NTDS\NTDS.DIT.

Q-14: What is the SYSVOL folder? The SYSVOL folder stores the server copy of the domain’s public files that must be shared for common access and replication throughout a domain. All AD databases are stored in a SYSVOL folder and it’s only created in an NTFS partition. The Active Directory Database is stored in the %SYSTEM ROOT%NDTS folder.

During the event, more than 80,000 attendees had access to free Wi-Fi at Fira Gran Via and over the four days nearly 81,000 Internet-connected devices generated a total of 19.1 terabytes of traffic.

A preliminary breakdown of the unprecedented volume of data exchanged revealed a 300 per cent year on year increase in the amount of traffic at the event, reflecting the performance and reliability of the high-density Wi-Fi network enabled by Cisco. Attendees predominantly used the Wi-Fi network to enable productivity and to stay in touch with their social networks; 33 percent of the traffic was used for highly-secure connections to business services such as email, closely followed by web browsing, Skype, Google Services and Facebook.

Fast Facts on the Cisco-based Mobile World Congress Wi-Fi network

• 80,880 Internet-enabled devices were connected, doubling the number from the 2013 Mobile World Congress;

• 1.2 gigabytes per second of peak Internet traffic;

• 19.1 terabytes of data – offloading 3G/4G traffic from mobile networks to provide an improved, integrated mobile experience for attendees;

• Five gigahertz (GHz) to 2.4 GHz ratio was 58 percent to 42 percent -- indicating a shift to higher adoption of five GHz devices;

• 280 gigabytes uploaded and transmitted via a single access point in the Mobile World Congress Media Village on Monday, Feb. 24, 2014; and

• By 10:00 a.m. on Feb. 24, 2014, the number of connections had surpassed the total number of connections on last year's network, ultimately reaching 22,126 peak-concurrent connections. Key Highlights

• Cisco worked with Fira de Barcelona to install a permanent Wi-Fi network covering 240,000 square meters of the Fira's Gran Via venue, the site of the annual Mobile World Congress.

• The Cisco Service Provider Wi-Fi solution allowed the GSMA to offer free high-speed Wi-Fi service to Mobile World Congress attendees at Fira Gran Via and allowed Fira to offer exhibitors Wi-Fi services in the eight exhibit halls.

• High-performance results demonstrate that carrier-grade Wi-Fi can complement cellular services in even the toughest environments. Delivering high-density Wi-Fi service in a venue as large as the Fira requires precise planning, monitoring and management. Cisco worked closely with the Fira in the months prior to the event to prepare the network for the four-day conference and exhibition.

4. Decide what to sync By default, windows 10 syncs all of your settings, themes, passwords, and other preferences with your Microsoft Account to bring a consistent environment for you if you log in the same account on different computers. But if this is not your thing or you just don’t want everything sync’d across board, Settings → Accounts → Sync your settings is the place to go.

5. Decide which browser to use If Microsoft Edge is yet good enough to be your primary browser for internet, it’s time to install Chrome or Firefox on your Windows 10. Otherwise, let’s customize your Edge a little to make it more personal and easy to use, things like theme, default search engine, start page, home page, bookmarks, etc.

6. Set default apps If you decided to keep using Chrome or Firefox as your browser or Adobe as default PDF reader, you need to set them as default apps in Settings → System → Default apps.

7. Check Windows Defender To make sure 1) real-time protection is on; and 2) version info is up to date. It’s the built-in anti-virus system that comes with Windows 10 so you save money on something else. Keep it running in good shape is important to your system.

8. Setting up OneDrive Since OneDrive is no longer using Online-Only mode, it’s important to know that if you have a large OneDrive you need to pay attention to your Internet usage. You don’t want to throttle your network just because you are downloading your whole OneDrive onto your new Windows 10 computer. Check the following post for more details.

9. Sign-in options Windows 10 has more sign-in options than any previous Windows. In addition to Password, Pin, Picture Password, you now can use your face to sign in using Microsoft’s Hello face recognition technology. It’s pretty cool but it also requires a 3-D depth camera to be functional. Unfortunately, not all laptops or tablets have that equipped at the moment.

• show controllers—Displays statistics for interface card controllers.

• show flash—Displays the layout and contents of flash memory.

• show buffers—Displays statistics for the buffer pools on the router.

• show memory summary—Displays memory pool statistics and summary information about the activities of the system memory allocator, and gives a block-by-block listing of memory use.

• show process cpu—Displays information about the active processes on the router.

• show stacks—Displays information about the stack utilization of processes and interrupt routines, and the reason for the last system reboot.

• show cdp neighbors—Provides reachability information for directly connected Cisco devices. This is an extremely useful tool for determining the operational status of the physical and data link layers. Cisco Discovery Protocol (CDP) is a proprietary data link layer protocol.