Choosing a San Francisco Dental Insurance Plan

Choosing a San Francisco Dental Insurance Plan

In the United States, there are a large number of Americans who are without dental insurance. Dental insurance is often the key to obtaining professional dental care. Without it, many are unable to afford a trip to the dentist. If you are currently without dental insurance, whether your employer does not offer it or if you are unemployed, you may want to consider obtaining your own dental insurance plan.

Before you can go out and purchase a dental insurance plan, there are a number of different factors that you should consider. Where you live is one of those factors. Where you live may have an impact on the dental insurance companies in which you are able to do business with. For instance, if you live in or around the San Francisco area, you will want to consider doing business with a San Francisco dental insurance company. A San Francisco dental insurance company is defined as a company that either operates out of the area or services it.

If you are currently unfamiliar with at least one San Francisco dental insurance company, you will need to start familiarizing yourself with all of your available options. To learn about dental insurance companies in the San Francisco area, you are advised to either pick up your local phone or use to internet to do the research. Whether you use your local phone book or the internet, you should easily be able to obtain the contact information of at least one San Francisco dental insurance company.

Once you have found a dental insurance company that you would like to do business with, you will then have to decide on a San Francisco dental insurance plan. You will find that most insurance companies have a number of different available plans for you to choose from. Sometimes there are so many San Francisco dental insurance plans to choose from that you may not know which one is right for you. Before officially choosing a San Francisco dental insurance plan, you are advised to research and examine each plan.

If, after examining each San Francisco dental insurance plan that is available, you are still unable to make a decision, you may want to consider seeking assistance from a dental insurance representative. Most dental insurance representatives would be more that willing to assist you with understanding which plan is the best one for your needs. However, before that assistance can be offered, you may need to provide your insurance representative with a little bit of background on yourself, your family, or your health.

Regardless of which San Francisco dental insurance plan you choose, you can still benefit from having one. All dental insurance plans, no matter how much or how little they cover, should be able to offer you assistance. Instead of having to suffer through another toothache or pay for your own dental work, you are encouraged to at least consider obtaining dental insurance. If you have never had dental insurance, you may be surprised with just how much money you can save.

Ashton Skylar is a writer for Free Insurance Quotes 4 You.com where you will discover great information on San Francisco Dental Insurance Plan and other related information.

Inexpensive Salsa Dance Classes in San Francisco

Dance SF is the top salsa dance school that caters to the needs of aspiring salsa dancers.

Our classes are only $50 for a 4-week dance program taught by experienced salsa dance instructors. IF you are looking for a location near you in the San Francisco Bay Area, check out http://www.dancesf.com/home.htm.

Whether you are young or old we have salsa dance classes for everyone! But you shouldn't only use those moves in the dance studio. Why not go out to a local salsa dance club and show off those new moves! It's a great way to improve upon your newly acquired skill but it's also a great way to mingle and meet new people.

While you're at the club, party it up! The best way to improve is to dance with everybody, everywhere, anytime. You're just starting out? You're not expected to be Fred Astaire! Dance with as many people as you possibly can, and don't be afraid to ask that great dancer that you see in the club for a dance, or for some pointers. When asking people more advanced than yourself, be mindful of Salsa Etiquette for Beginners (which you'll learn in your Dance Class at www.dancesf.com). Even if you have a partner, don't only dance with them! It pays to learn to lead and follow from a variety of people, spread yourself around. You will learn FASTER!

While taking dance classes make sure you at least get out to a salsa dance club at least once a week (preferably more). Not only is it a blast to go out dancing, but in the beginning it can help reinforce those things you learn in class. Nothing is like some real world practice. It also helps you get used to the music which is played in the clubs, which by and large, is faster than what you will find in your typical salsa class! Check out Beginner Friendly Clubs listed on www.dancesf.com to find places to go out that are better bets for beginner dancers in the San Francisco Bay Area!

Evan Margolin is the president of DanceSF, the premiere salsa dancing academy in the San Francisco Bay Area. Learn to dance at the studio or in your own home with his Learn to Salsa DVDs. Find out more by visiting http://www.DanceSF.com

Cisco CCNA / CCNP Certification Exam Review: Protocol Basics

To earn your Cisco CCNA certification and pass the BSCI CCNP exam, you have to know your protocol basics like the back of your hand! To help you review these important concepts, here's a quick look at the basics of RIPv1, RIPv2, IGRP, and EIGRP.

RIPv1: Broadcasts updates every 30 seconds to the address 255.255.255.255. RIPv1 is a classful protocol, and it does not recognize VLSM, nor does it carry subnet masking information in its routing updates. Update contains entire RIP routing table. Uses Bellman-Ford algorithm. Allows equal-cost load-balancing by default. Max hop count is 15. Does not support clear-text or MD5 authentication of routing updates. Updates carry 25 routes maximum.

RIPv2: Multicasts updates every 30 seconds to the address 224.0.0.9. RIPv2 is a classless protocol, allowing the use of subnet masks. Update contains entire RIP routing table. Uses Bellman-Ford algorithm. Allows equal-cost load-balancing by default. Max hop count is 15. Supports clear-text and MD5 authentication of routing updates. Updates carry 25 routes maximum.

IGRP: Broadcasts updates every 90 seconds to the address 255.255.255.255. IGRP is a Cisco-proprietary protocol, and is also a classful protocol and does not recognize subnet masking. Update contains entire routing table. Uses Bellman-Ford algorithm. Equal-cost load-balancing on by default; unequal-cost load-sharing can be used with the variance command. Max hop count is 100.

EIGRP: Multicasts full routing table only when an adjacency is first formed. Multicasts updates only when there is a change in the network topology, and then only advertises the change. Multicasts to 224.0.0.10 and allows the use of subnet masks. Uses DUAL routing algorithm. Unequal-cost load-sharing available with the variance command.

By mastering the basics of these protocols, you're laying the foundation for success in the exam room and when working on production networks. Pay attention to the details and the payoff is "CCNA" and "CCNP" behind your name!

Chris Bryant, CCIE #12933, is the owner of The Bryant Advantage , home of free CCNA and CCNP tutorials! Pass the CCNA exam with Chris Bryant!

Cisco CCNA / CCNP / BCMSN Exam Review: Trunking And Trunking Protocols

To earn your CCNA or CCNP certification, you've got to understand the basics of trunking. This isn't just a CCNA topic - you must have an advanced understanding of trunking and etherchannels to pass the BCMSN exam and earn your CCNP as well. Before we address those advanced topics, though, you need to master the fundamentals!

A trunk allows inter-VLAN traffic to flow between directly connected switches. By default, a trunk port is a member of all VLANs, so traffic for any and all VLANs can travel across this trunk. That includes broadcast traffic!

The default mode of a switch port does differ between models, so always check your documentation. On Cisco 2950 switches, every single port is in dynamic desirable mode by default, meaning that every port is actively attempting to trunk. On these switches, the only action needed from us is to physically connect them with a crossover cable. In just a few seconds, the port light turns green and the trunk is up and running. The command show interface trunk will verify trunking.

How does the receiving switch know what VLAN the frame belongs to? The frames are tagged by the transmitting switch with a VLAN ID, reflecting the number of the VLAN whose member ports should receive this frame. When the frame arrives at the remote switch, that switch will examine this ID and then forward the frame appropriately.

There are two major trunking protocols you must understand and compare successfully, those being ISL and IEEE 802.1Q. Let's take a look at the details of ISL first.

ISL is a Cisco-proprietary trunking protocol, making it unsuitable for a multivendor environment. That's one drawback, but there are others. ISL will place both a header and trailer onto the frame, encapsulating it. This increases the overhead on the trunk line.

You know that the default VLAN is also known as the "native VLAN", and another drawback to ISL is that ISL does not use the concept of the native VLAN. This means that every single frame transmitted across the trunk will be encapsulated.

The 26-byte header that is added to the frame by ISL contains the VLAN ID; the 4-byte trailer contains a Cyclical Redundancy Check (CRC) value. The CRC is a frame validity scheme that checks the frame's integrity.

In turn, this encapsulation leads to another potential issue. ISL encapsulation adds 30 bytes total to the size of the frame, potentially making them too large for the switch to handle. (The maximum size for an Ethernet frame is 1518 bytes.)

IEEE 802.1q differs substantially from ISL. In contrast to ISL, dot1q does not encapsulate frames. A 4-byte header is added to the frame, resulting in less overhead than ISL. If the frame is destined for hosts residing in the native VLAN, that header isn't added. Since the header is only 4 bytes in size, and isn't even placed on every frame, using dot1q lessens the chance of oversized frames. When the remote port receives an untagged frame, the switch knows that these untagged frames are destined for the native VLAN.

Knowing the details is the difference between passing and failing your CCNA and CCNP exams. Keep studying, get some hands-on practice, and you're on your way to Cisco certification success!

Chris Bryant, CCIE #12933, is the owner of The Bryant Advantage , home of free CCNA and CCNP tutorials! Pass the CCNA exam with Chris Bryant!

Cisco CCNA / CCNP Home Lab Tutorial: The 2503 Router

I know from experience that part of the excitement and anxiety of putting together your own CCNA / CCNP home lab is deciding what to buy! While you can make a workable home lab out of almost any combination of Cisco routers and switches, some routers are better suited for home lab work than others because they can fill multiple roles.

When you buy CCNA or CCNP "lab kits" - bundles of routers and switches - you can get a little confused about whether you're getting a good deal. One router I get asked about quite a bit is the 2503.

2503 routers are fantastic for CCNA and CCNP home labs. They come with two serial interfaces, allowing you to connect one interface directly to another router (you'll need a DTE/DCE cable for that, too) while connecting another to a frame relay switch if you like. If you don't have a frame relay switch, you can connect a 2503 directly to two other routers via the serial interfaces.

You also have an AUI port, which requires a transceiver to operate as your Ethernet interface. Transceivers are pretty cheap and readily available from Cisco resellers and ebay vendors, so pick one up for each 2503 you decide to buy.

2503 routers also come with a BRI interface. Even though you may not have an ISDN simulator right now, you may choose to add one later. That makes a 2503 a great bet for future lab expansion.

All in all, 2503 routers are great for your CCNA / CCNP home lab. They run about $125 each on ebay, or less, so they're also very affordable. There's no better training than training on your own CCNA or CCNP home lab, and you can always sell the equipment later if you like. Basically, you're renting the routers and switches, and the experience you get by working with the real deal is invaluable.

Chris Bryant, CCIE #12933, is the owner of The Bryant Advantage (http://www.thebryantadvantage.com), home of free CCNA and CCNP tutorials! For my FREE "How To Pass The CCNA" or "CCNP" ebook, visit the website and download your copies. Get your CCNA study guide from The Bryant Advantage!

Cisco CCNP / BCMSN Exam Tutorial: Multicasting And Reserved Addresses

Ever since you picked up your first CCNA book, you've heard about multicasting, gotten a fair idea of what it is, and you've memorized a couple of reserved multicasting addresses. Now as you prepare to pass the BCMSN exam and become a CCNP, you've got to take that knowledge to the next level and gain a true understanding of multicasting. Those of you with an eye on the CCIE will truly have to become multicasting experts!

Having said that, we're going to briefly review the basics of multicasting first, and then future tutorials will look at the different ways in which multicasting can be configured on Cisco routers and switches.

What Is Multicasting?

A unicast is data that is sent from one host to another, while a broadcast is data sent from a host that is destined for "all" host addresses. By "all", we can mean all hosts on a subnet, or truly all hosts on a network.

There's a quite a bit of a middle ground there! A multicast is that middle ground, as a multicast is data that is sent to a logical group of hosts, called a multicast group. Hosts that are not part of the multicast group will not receive the data.

Some other basic multicasting facts:

There's no limit on how many multicast groups a single host can belong to.

The sender is usually unaware of what host devices belong to the multicast group.

Multicast traffic is unidirectional. If the members of the multicast group need to respond, that reply will generally be a unicast.

The range of IP addresses reserved for multicasting is the Class D range, 224.0.0.0 - 239.255.255.255.

That range contains a couple of other reserved address ranges.

224.0.0.0 - 224.0.0.255 is reserved for network protocols only on a local network segment. Packets in this range will not be forwarded by routers, so these packets cannot leave the segment.

Just as Class A, Class B, and Class C networks have private address ranges, so does Class D. The Class D private address range is 239.0.0.0 - 239.255.255.255. Like the other private ranges, these addresses can't be routed, so they can be reused from one network to another.

The remaining addresses fall between 224.0.1.0 and 238.255.255.255. That's the "normal" range of multicast addresses. These addresses can be routed, so they must be unique and should not be duplicated from one network to the next.

In my next BCMSN / CCNP multicasting tutorial, we'll take a look at the different ways in which Cisco routers and switches interact to forward multicast traffic.

Chris Bryant, CCIE #12933, is the owner of The Bryant Advantage (http://www.thebryantadvantage.com), home of free CCNP and CCNA tutorials! For my FREE "How To Pass The CCNA" or "CCNP" ebook, visit the website and download your copies. Pass your CCNP exam with The Bryant Advantage!

Cisco CCNP / BSCI Exam Tutorial: The Passive Interface Command And OSPF

To pass the BSCI exam and become a CCNP, you have to be aware of the proper use of passive interfaces. You learned about passive interfaces in your CCNA studies, but here we'll review the basic concept and clear up one misconception regarding passive interfaces and OSPF.

Configuring an interface as passive will still allow the interface to receive routing updates, but the interface will no longer transmit them. While the command itself would make you think this command will be applied at the interface level, that is not the case. Below, we'll configure ethernet0 as a RIP passive interface.

R1(config)#router rip

R1(config-router)#passive-interface ethernet0

Ethernet0 will no longer send RIP routing updates, but will accept them.

The passive interface concept is clear enough with RIP, IGRP, and EIGRP - all protocols that send routing update packets. But OSPF doesn't send routing update packets - OSPF sends link state advertisements. It's the inability of the passive interface command to stop LSAs that lead many to think that passive interfaces cannot be used with OSPF.

Even though OSPF does not sent "routing updates" in the form that RIP, IGRP, and EIGRP do, you can still configure an OSPF-enabled interface as passive in order to prevent OSPF traffic from exiting or entering that interface. No OSPF adjacency can be formed if one of the interfaces involved is a passive interface, and if you configure an OSPF-enabled interface as passive where an adjacency already exists, the adjacency will drop almost immediately.

Let's see that in action. R1 and R2 have an existing OSPF adjacency over their Ethernet interfaces. In an effort to reduce routing traffic, R1's e0 interface is configured as passive. The adjacency drops right away.

R1(config)#router ospf 1

R1(config-router)#passive-interface ethernet0

18:31:11: %OSPF-5-ADJCHG: Process 1, Nbr 2.2.2.2 on Ethernet0 from FULL to DOWN, Neighbor Down: Interface down or detached

Knowing how to use the passive interface command is a vital part of being a CCNP, and of being a master networker. Good luck to you in both of these pursuits!

Chris Bryant, CCIE #12933, is the owner of The Bryant Advantage , home of free CCNA and CCNP tutorials! Pass the CCNA exam with Chris Bryant!

Cisco CCNA Exam Tutorial: Loopback Interfaces

As a CCNA candidate, you most likely have some background in PC hardware and workstation support. If so, you're already familiar with loopback interfaces, particularly 127.0.0.1, the loopback address assigned to a PC.

When you're learning all about the different physical interfaces for your CCNA exam - serial, ethernet, and BRI, among others - there's one logical interface you need to know about, and that is - you guessed it! - the loopback interface.

What isn't as immediately apparent is why we use loopback interfaces on routers and switches to begin with. Many of the Cisco router features that can use loopbacks are intermediate and advanced features that you'll learn about in your CCNP and CCIE studies, but these features all come back to one basic concept: If the loopback interface on a router is down, that means the router is unavailable as a whole.

In contrast, a physical interface being down does not mean the router itself is out of commission. A router's ethernet port can go down, but the other physical interfaces on that router are still operational. Since a loopback interface is logical, there's nothing physical that can go wrong with it.

As I mentioned, you'll learn different Cisco router and switch features that utilize loopback interfaces as you climb the Cisco certification ladder. There's one misconception about Cisco loopback interfaces that you want to get clear on now, though. You?re probably familiar with loopback interfaces on a PC, and may even know that the address range 127.0.0.0 is reserved for loopback addressing.

Note that this reserved address range does not apply to loopbacks on Cisco devices, however. If you attempt to assign an address from this range to a Cisco loopback interface, you get this result:

R1#conf t

Enter configuration commands, one per line. End with CNTL/Z.

R1(config)#interface loopback0

R1(config-if)#ip address 127.0.0.2 255.255.255.0

Not a valid host address - 127.0.0.2

R1(config-if)#ip address 127.1.1.1 255.255.255.0

Not a valid host address - 127.1.1.1

The range 127.0.0.0 is reserved for host loopbacks (such as PCs), not routers or switches. The most commonly used address from this range is 127.0.0.1 ? if you can?t ping that on a workstation, that means you can?t ping yourself, which means there?s a problem with the TCP/IP install itself.

Keep these details in mind on the exam and in the workplace, and you?re on your way to CCNA exam success!
Chris Bryant, CCIE #12933, is the owner of The Bryant Advantage (http://www.thebryantadvantage.com ), home of free CCNA and CCNP tutorials, and The Ultimate CCNA and CCNP Study Packages. For a copy of his FREE "How To Pass The CCNA" or "CCNP" ebook, visit the website and download copies! Our new RSS feed gives you free Cisco questions daily!

Cisco CCNP Certification/BSCI Exam Tutorial: ISIS Hellos And Adjacencies

In my last ISIS tutorial, I mentioned that while ISIS and OSPF are both link state protocols, their actual operation differs greatly. To pass the BSCI exam and earn your CCNP, you'll need to know these differences! Today, we'll take a look at ISIS Hello types and the adjacency types that form through the use of these Hellos.

Hello packets have been mentioned several times with ISIS, and with good reason. Hello packets are the heartbeat of OSPF and ISIS when heartbeats are no longer heard from a neighbor, that adjacency will be dropped. A major difference between OSPF and ISIS is that OSPF has one type of Hello packet, where ISIS actually has three!

An ES Hello (ESH) is send by all End Systems, and all IS devices listen for this Hello. This is how a router (IS) discovers a host (ES).

An IS Hello (ISH) announces the presence of an IS. An IS Hello is sent by all IS devices, and End Systems listen for these hellos.

An IS-to-IS Hello (IIH) is used by an IS to discover other ISes and to form adjacencies with them.

An interesting side note: A router will send an IIH to another router on the link to form or maintain an adjacency, but it will still send an ISH as well in case there are end systems located on that segment.

ISIS and OSPF both create and maintain adjacencies with the Hello packet. Let's take a look at the rules regarding ISIS adjacencies as well as the adjacency types.

L1 and L2 Hellos are different messages, so an L1 router must exchange Hellos with another L1 router to form an adjacency, just as L2 routers form adjacencies with L2 routers. L1 routers can only form an adjacency with an L2 router if one of the two routers involved is actually an L1/L2 router.

L1 routers must be in the same area in order to form an adjacency. The Hello timers, as well as the MTU, must match between the interfaces used to form the adjacency.

That's a lot of L1, L2, and L1/L2, isn't it? Let's review the adjacencies each router type can form:

L1: Can form adjacency with any L1 in the same area and any L1/L2 in the same area.

L2: Can form adjacency with any L2 in any area, and with an L1/L2 in any area.

L1/L2: Can form adjacency with any L1 in the same area, L1/L2 in any area, and L2 in any area.

Knowing the similarities and differences regarding ISIS and OSPF is vital for CCNP exam success. Take your time, master the fundamentals, and before long the magic letters ?CCNP? are behind your name and on your resume!
Chris Bryant, CCIE #12933, is the owner of The Bryant Advantage (http://www.thebryantadvantage.com). For a copy of his FREE "How To Pass The CCNA" or "CCNP" ebook, visit the website and download your copies! Daily exam questions now available through RSS feed!