Telephone company and internet.

yacocati wrote:

Thanks,
So You say it’s the best, contracting a data pack with my tel. CompanY in Spain And In adiction use a cómpany in Vietnam only for calls?

No, I mean that you use the Spain SIM card with roaming data packet only for the first days in Vietnam.
After you checked in and recover, you can go to a phone shop and exchange your Spain SIM card by a Vietnamese SIM card.
From then you can call with Spain by Zalo, Whatsapp, etc. via 3G/4G/Wifi internet connection.
The best solution would be a dual SIM card cell phone.
So you can use the Vietnamese SIM card for voice and/or data in Vietnam and the Spain SIM card with roaming data packet for receive TAN of your Spain bank and credit card transactions.

yacocati wrote:

What is the best company to have with them contracted the line for cellular and for internet at home, also a good cover to use internet in my Smart phone.?

If you're going to live in a serviced apartment, WiFi is included in the rent so there's no need to bother. 

For the phone, I would just get a Vietnam SIM.  Whether a dual SIM card phone is more convenient is a matter of preference.  Not to us.  We call, text, and receive both from the US every other day on our phones (not always free calls).  I also call and receive calls to all networks within Vietnam almost daily on my phone.  We only have Vietnam phone numbers, and we use Viettel for both of our phones.  Have yet to encounter any difficulties.

My spouse has a 4G prepaid data plan which we put 1M in once a year.  Last month when the year was up, he had 102K left.

I have a 4G postpaid data plan that costs between 105K - 115K every month, but as mentioned above, I make call and text to all networks very frequently, and I don't skim on Internet usage when we're from home or when Wifi is not available.  We don't walk around checking on FB and the likes, but if we need Internet, we turn on cellular and use it.

Jim-Minh wrote:

If you receive Wi-Fi as part of the rent package do you have to worry about security? Shouldn't you do all secure transactions on a private connection?

If you have a serviced apartment where Wifi is included, it is very individual. If it has a good WLAN router with modern encryption (at least WPA2), the WLAN password (security key) is secure and the router itself is well password protected, security is fine. However, this is rarely the case, since the WLAN password is usually very simple (e.g. apartment name) and cannot be changed.
In one apartment I had a router that I could access via LAN (password: 12345). At least I could change the settings in the router so that it was more secure than before.

If you have to organize the Wifi yourself, you can set the WLAN password yourself when someone comes and installs the router.

I personally use my mobile phone as a Wifi hotspot for my computer whenever I do financial transactions.

By the way, some antivirus secuity application, issue a WLAN security key warning if the key is too short.

Ciambella wrote:

Perhaps a separate WiFi hotspot would be good for your work, Jim-Minh, such as this one that we use: Portable Wifi hotspot

We've always taken it with us when travelling to other SEA countries (local SIM).  We had 4 cell phones and 1 laptop on it at the same time every day when we were in Thailand last, and it handled the job beautifully.

That looks like a very convenient and secure way of doing that job as well as having other functionality. The Viet price is cheaper than what I can get through Amazon in Dallas. I've seen mention of Internet service for such a device in Vietnam at a very good price. That answers a number of questions. Thanks very much.