Update README.md

README.md

@@ -17,7 +17,7 @@ We will use <a href="https://libreswan.org/" target="_blank">Libreswan</a> as th
 
 ## Requirements
 
-A newly created <a href="https://aws.amazon.com/ec2/" target="_blank">Amazon EC2</a> instance, using these AMIs: (Follow <a href="https://blog.ls20.com/ipsec-l2tp-vpn-auto-setup-for-ubuntu-12-04-on-amazon-ec2/#vpnsetup" target="_blank">this link</a> for instructions)
+A newly created <a href="https://aws.amazon.com/ec2/" target="_blank">Amazon EC2</a> instance, using these AMIs: (See <a href="https://blog.ls20.com/ipsec-l2tp-vpn-auto-setup-for-ubuntu-12-04-on-amazon-ec2/#vpnsetup" target="_blank">instructions</a>)
 - <a href="http://cloud-images.ubuntu.com/trusty/current/" target="_blank">Ubuntu 14.04 (Trusty)</a> or <a href="http://cloud-images.ubuntu.com/precise/current/" target="_blank">12.04 (Precise)</a>
 - <a href="https://wiki.debian.org/Cloud/AmazonEC2Image/Jessie" target="_blank">Debian 8 (Jessie) EC2 Images</a>
 - <a href="https://aws.amazon.com/marketplace/pp/B00O7WM7QW" target="_blank">CentOS 7 (x86_64) with Updates HVM</a>
@@ -36,7 +36,7 @@ OpenVZ VPS users should instead try <a href="https://github.com/Nyr/openvpn-inst
 
 <a href="https://blog.ls20.com/ipsec-l2tp-vpn-auto-setup-for-ubuntu-12-04-on-amazon-ec2/#gettingavps" target="_blank">**&raquo; I want to run my own VPN but don't have a server for that**</a>
 
-:warning: **DO NOT run these scripts on your PC or Mac! They are meant to be run on a dedicated server or VPS!**
+:warning: **DO NOT run these scripts on your PC or Mac! They should only be run on a dedicated server or VPS!**
 
 ## Installation
 
@@ -63,7 +63,7 @@ nano -w vpnsetup_centos.sh
 /bin/sh vpnsetup_centos.sh
 ```
 
-If unable to download via `wget`, you may open [vpnsetup.sh](vpnsetup.sh) (or [vpnsetup_centos.sh](vpnsetup_centos.sh)) and click the **`Raw`** button on the right. Press `Ctrl+A` to select all, `Ctrl-C` to copy, then paste into your favorite editor.
+If unable to download via `wget`, you may alternatively open [vpnsetup.sh](vpnsetup.sh) (or [vpnsetup_centos.sh](vpnsetup_centos.sh)) and click the **`Raw`** button. Press `Ctrl+A` to select all, `Ctrl-C` to copy, then paste into your favorite editor.
 
 ## Next Steps
 
@@ -73,30 +73,30 @@ Enjoy your very own VPN! :sparkles::tada::rocket::sparkles:
 
 ## Important Notes
 
-For **Windows users**, a <a href="https://documentation.meraki.com/MX-Z/Client_VPN/Troubleshooting_Client_VPN#Windows_Error_809" target="_blank">one-time registry change</a> is required if the VPN server and/or client is behind NAT (e.g. home router). Also, make sure that `CHAP` is enabled under "Allow these protocols" in the "Security" tab of VPN connection properties. (<a href="https://github.com/hwdsl2/setup-ipsec-vpn/issues/7#issuecomment-182571109" target="_blank">Ref</a>)
+For **Windows users**, a <a href="https://documentation.meraki.com/MX-Z/Client_VPN/Troubleshooting_Client_VPN#Windows_Error_809" target="_blank">one-time registry change</a> is required if the VPN server and/or client is behind NAT (e.g. home router). In addition, make sure `CHAP` <a href="https://github.com/hwdsl2/setup-ipsec-vpn/issues/7#issuecomment-182571109" target="_blank">is enabled</a> under "Allow these protocols" in the "Security" tab of VPN connection properties.
 
-**Android 6 (Marshmallow) users**: After install, edit `/etc/ipsec.conf` and append `,aes256-sha2_256` to both `ike=` and `phase2alg=`. Also add a new line `sha2-truncbug=yes`. Start lines with two spaces. Finally, run `service ipsec restart`.
+**Android 6 (Marshmallow) users**: After install, edit `/etc/ipsec.conf` and append `,aes256-sha2_256` to both `ike=` and `phase2alg=`. Then <a href="https://libreswan.org/wiki/FAQ#Android_6.0_connection_comes_up_but_no_packet_flow" target="_blank">add a new line</a> `sha2-truncbug=yes`. Indent lines with two spaces. Finally, run `service ipsec restart`.
 
-**iPhone/iPad users**: In iOS settings, choose `L2TP` (instead of `IPSec`) for the VPN type. In case you're unable to connect, edit `ipsec.conf` and replace `rightprotoport=17/%any` with `rightprotoport=17/0`. Then restart `ipsec` service.
+**iPhone/iPad users**: In iOS settings, choose `L2TP` (instead of `IPSec`) as the VPN type. In case you are unable to connect, edit `ipsec.conf` and replace `rightprotoport=17/%any` with `rightprotoport=17/0`. Then restart `ipsec` service.
 
 If you wish to enable multiple VPN users with different credentials, just <a href="https://gist.github.com/hwdsl2/123b886f29f4c689f531" target="_blank">edit a few lines</a> in the scripts.
 
 Clients are configured to use <a href="https://developers.google.com/speed/public-dns/" target="_blank">Google Public DNS</a> when the VPN is active. To change, set `ms-dns` in `options.xl2tpd`.
 
-If using Amazon EC2, open these ports in the server's security group: **UDP 500 & 4500**, and **TCP port 22** (optional, for SSH).
+If using Amazon EC2, open **UDP ports 500 & 4500** and **TCP port 22** (optional, for SSH) in the instance's <a href="https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-network-security.html" target="_blank">security group</a>.
 
-If you configured a custom SSH port or wish to allow other services, edit the IPTables rules in the scripts before using.
+If you configured a custom SSH port or wish to allow other services, edit the IPTables rules within the scripts before using.
 
 The scripts will backup your existing config files before making changes, to the same folder with `.old-date-time` suffix.
 
 ## Upgrading Libreswan
 
-You may use [vpnupgrade_Libreswan.sh](vpnupgrade_Libreswan.sh) (for Ubuntu/Debian) or [vpnupgrade_Libreswan_centos.sh](vpnupgrade_Libreswan_centos.sh) (for CentOS/RHEL) to upgrade <a href="https://libreswan.org/" target="_blank">Libreswan</a> to a newer version. Check and update the `SWAN_VER` variable on top of the scripts as necessary.
+The additional scripts [vpnupgrade_Libreswan.sh](vpnupgrade_Libreswan.sh) and [vpnupgrade_Libreswan_centos.sh](vpnupgrade_Libreswan_centos.sh) can be used to periodically upgrade Libreswan to the latest version. Check the <a href="https://libreswan.org" target="_blank">official website</a> and update the `SWAN_VER` variable as necessary.
 
 ## Bugs & Questions
 
 - Have a question? Please first search other people's comments <a href="https://gist.github.com/hwdsl2/9030462#comments" target="_blank">in this Gist</a> and <a href="https://blog.ls20.com/ipsec-l2tp-vpn-auto-setup-for-ubuntu-12-04-on-amazon-ec2/#disqus_thread" target="_blank">on my blog</a>.
-- For Libreswan related questions, you may ask on the <a href="https://lists.libreswan.org/mailman/listinfo/swan" target="_blank">mailing list</a>, or check out the <a href="https://libreswan.org/wiki/Main_Page" target="_blank">official wiki</a>.
+- Ask Libreswan (IPsec) related questions <a href="https://lists.libreswan.org/mailman/listinfo/swan" target="_blank">on this mailing list</a>, or check out its <a href="https://libreswan.org/wiki/Main_Page" target="_blank">official wiki</a>.
 - If you found a reproducible bug, open a <a href="https://github.com/hwdsl2/setup-ipsec-vpn/issues" target="_blank">GitHub Issue</a> to submit a bug report.
 
 ## Copyright and License